Recommendation for Update ofNepal National Building CodeFinal ReportJuly, 2009Submitted by:MULTI Disciplinary Consultants ...
Recommendation for Update of Nepal NationalBuilding Code: Final ReportContentsExecutive Summary .............................
3.25 Capacity of personnel, qualification....................................................................................
5.8 Review of NNBC 208: 1994 - Plumbing and Sanitation ................................................... 515.8.1 Water S...
Abbreviations:ADRC Asian Disaster Reduction CenterADPC Asian Disaster Preparedness CenterASTM American Society for Testing...
Executive SummaryIntroductionThe assignment for preparation of the recommendation report for Updating the National Buildin...
 Anomalies of NNBC Frequency of Updates of Codes and Responsibilities Aesthetics, Change in Occupancy and Structural Sa...
Mandatory Application of Bylaws through out the countryThe Building Byelaws are by legislation applicable in the areas of ...
 The provisions in the Codes have several ambiguous statements, Incomplete sentences,reference to the Indian Standard Cod...
Recommendation for Update of Nepal NationalBuilding Code: Final Report1 Introduction1.1 GeneralThe current assignment of p...
1.5 Scope of WorksThe scope of works related to above mentioned Objectives is: Discussion and interaction with ERRRP/DUDB...
SN Position Name Firm Input,MMTask Assignment2 TLStructuralEngineerDr. PremNathMaskeyMulti 1 Discussion and interactionRev...
The revision and updating of NNBC are not done in a regular basis since there is nodedicated institution for this job. The...
2 Current Practices2.1 National PolicyNepal is considered one of most vulnerable country for earthquakes. The recent earth...
 Inspection of Construction Progress by Municipality Staff Certification of Completion jointly by the Licensed Designer ...
requirement of NNBC and who does certify the compliance since design and constructionsupervision documents and As-Built Dr...
 National Bureau of Standards and Metrology is responsible for the certification ofstandards and constituents of codes an...
The requirements of these guidelines shall be followed at minimum. The designer ishowever free to exercise more stringent ...
3.2 Hierarchy of Act, Bylaws, Codes and Standards, and ReferencesThere is a gross confusion about the hierarchy and priori...
 Design Parameters as:- Settlement, deformation, strength, crack opening- Static and dynamic analysis- Retrofitting of ex...
3.11 Relationship between Aesthetics and Structural SafetyIn several cases, the architectural shape and size artificially ...
3.17 Building Material Handling, storage and useThe Safety of public and labor during material handling, storage and use i...
3.24 EducationThe education in Engineering Colleges is based on course books and seldom referred to theNNBC or other codes...
4.4 Use of NNBC 205: MRTThe municipality licensed designers widely use these codes for all construction beyond thelimit of...
researches in the area of Earthquake Engineering have resulted into sophisticated seismiccodes in developed countries. The...
The practice of developing, approving, and enforcing Building Codes is different from onecountry to another. In some natio...
 Ambiguous statements shall be removed unless a necessary clarification is provided toavoid the scope for misinterpretati...
The special emphasis on the need for application of the code in conjunction with IS 4326 –1993, under sub-heading – Relate...
It is necessary to include the general principle adopted regarding the ground motion, itsfeatures in relation with the ear...
0.9 times dead load, as well as in combination with dead load and 1.3 times live load. Thevalue of 1.25 is too low in view...
design response spectrum, in which the ordinate of the basic response spectrum for thenatural time period, is multiplied b...
exceedence in 50 years with a return period of 2500 years and 10% probability ofexceedence in 50 years with a return perio...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyach...
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Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyachhyon

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Nnbc update reco-final july 2009 - Recommendation for update of National Building Code of Nepal, Edited by Badan Lal Nyachhyon

  1. 1. Recommendation for Update ofNepal National Building CodeFinal ReportJuly, 2009Submitted by:MULTI Disciplinary Consultants (P) Ltd.P.O. Box 5720, Kathmandu, NepalTel: (977)-1-5525076/5529304, Fax: (977)-1- 5523103E-mail: mdc@multinepal.com.np, Web Site: www.MultiNepal.com/mdcin associaton withK.D. Associates (P) Ltd.P.O. Box 686Tel: 425263, Fax: 4215341E-mail: kdapl@info.com.np,Web: www.hurarah.com.npandKhwopa Engineering CollegeLibali, Bhaktapur-2P.O. Box 84, Bhaktapur, NepalTel: 6614794, 6614798E-mail: khec@wlink.com.npThe Government of NepalMinistry of Physical Planning and WorksEarthquake Risk Reduction and Recovery PreparednessProgramme for Nepal(UNDP/ERRRP-Project: NEP/07/010)
  2. 2. Recommendation for Update of Nepal NationalBuilding Code: Final ReportContentsExecutive Summary ........................................................................................................................ 61 Introduction......................................................................................................................... 101.1 General ................................................................................................................................... 101.2 The Project ............................................................................................................................. 101.3 The Assignment...................................................................................................................... 101.4 Objectives of the Assignment ................................................................................................ 101.5 Scope of Works ...................................................................................................................... 111.6 Methodology .......................................................................................................................... 111.7 The Project Team, Inputs and responsibilities ....................................................................... 111.8 Interaction with the Target Groups ........................................................................................ 121.9 Major Findings ....................................................................................................................... 122 Current Practices................................................................................................................ 142.1 National Policy....................................................................................................................... 142.2 Implementation of NNBC by Municipalities......................................................................... 142.3 Building Permit Process in LSMC......................................................................................... 142.4 Building Permit Process in KMC........................................................................................... 152.5 Data and information on building code implementation........................................................ 152.5.1 Government Buildings by DUDBC ........................................................................ 152.5.2 Practice in Municipalities........................................................................................ 162.6 Institutional Arrangements for Implementation of NNBC .................................................... 162.7 Jurisdiction of Application of NNBC..................................................................................... 172.8 Subscribed methods (PWD) of Seismic design consideration............................................... 173 Consideration of Problems and Issues of NNBC Application and Construction ......... 183.1 The Codes............................................................................................................................... 183.2 Hierarchy of Act, Bylaws, Codes and Standards, and References......................................... 193.3 Building bylaws...................................................................................................................... 193.4 Code Structure and Nepal Standards...................................................................................... 193.5 Need for Unified Code ........................................................................................................... 193.6 Criticism of NNBC................................................................................................................. 193.7 Family of Codes ..................................................................................................................... 203.8 Frequency of Update .............................................................................................................. 203.9 Commentary on Codes and Standards ................................................................................... 203.10 Conservation of Historic Building, Aesthetics, Planning Codes ........................................... 203.11 Relationship between Aesthetics and Structural Safety......................................................... 213.12 Change in Occupancy............................................................................................................. 213.13 High Rise Buildings ............................................................................................................... 213.14 Detailing of Joints .................................................................................................................. 213.15 Quality Monitoring and Advertisement Market..................................................................... 213.16 Supervision of Construction Works ....................................................................................... 213.17 Building Material Handling, storage and use......................................................................... 223.18 Specification of other Materials not mentioned in NNBC..................................................... 223.19 Mechanism for addressing Technical issues and data bank................................................... 223.20 Participation of masons, stakeholders, owners....................................................................... 223.21 Info dissemination and Interactions ....................................................................................... 223.22 Construction Safety................................................................................................................ 223.23 Ownership of Design and Intellectual Property rights ........................................................... 223.24 Education................................................................................................................................ 23
  3. 3. 3.25 Capacity of personnel, qualification....................................................................................... 233.26 Licensing of Skill Labor......................................................................................................... 234 Implementation of Codes and Standards ......................................................................... 234.1 Water Supply and Sanitation.................................................................................................. 234.2 Electrical Code ....................................................................................................................... 234.3 Fire Safety Code..................................................................................................................... 234.4 Use of NNBC 205: MRT ....................................................................................................... 245 Review of NNBC ................................................................................................................. 245.1 Review of NBC 000: 1994 State-Of-The Art Design And NBC 105: 1994 Seismic DesignOf Buildings In Nepal ............................................................................................................ 245.1.1 General .................................................................................................................... 245.1.2 NNBC 000: 1994 Requirements For State-Of-The Art Design .............................. 255.1.3 NNBC 105: 1994 Seismic Design Of Buildings In Nepal ...................................... 275.2 Review of NNBC 101, 102, 103, 104, 106, 108, 109 (Loads, Occupancy, SiteConsideration, Unreinforced Masonry) ............................................................................. 355.2.1 NNBC 101:1994: Materials Specifications............................................................. 355.2.2 NNBC 102:1994: Unit Weight of Materials ........................................................... 365.2.3 NNBC 103:1994: Occupancy Load (Imposed Load).............................................. 365.2.4 NNBC 104:1994: Wind Load ................................................................................. 375.2.5 NNBC 106:1994: Snow Load ................................................................................. 385.2.6 NNBC 108: 1994 Site Consideration...................................................................... 405.2.7 NNBC 109: Masonry (Unreinforced) ..................................................................... 415.3 Review of NNBC: 107 (Fire Code)...................................................................................... 425.3.1 General .................................................................................................................... 425.3.2 Main Objectives and Purpose of Building Codes ................................................... 425.3.3 Compliance to the Fire Code of Nepal.................................................................... 435.3.4 Major Drawback...................................................................................................... 435.3.5 Requirement of Fire Safety in Building Codes ....................................................... 435.4 Review of NNBC: 110, 111, 112, 113, 114 (Masonry, PCC, Materials, ConstructionSafety).................................................................................................................................... 445.4.1 NNBC 110: Plain and Reinforced Concrete..................................................................... 445.4.2 NNBC-111: 1994: Steel....................................................................................................... 445.4.3 NNBC-112: Timber 1994.................................................................................................... 455.4.4 NNBC-113: Aluminum 1994.............................................................................................. 455.4.5 NNBC 114:1994 CONSTRUCTION SAFETY ................................................................ 465.5 Review of NNBC: 201, 202, 203, 204, 205 (MRT, Low Strength and Earthen Buildings)................................................................................................................................................ 465.5.1 General .................................................................................................................... 465.5.2 NNBC 201: Mandatory Rules Of Thumb - Reinforced Concrete Buildings withMasonry Infill.......................................................................................................... 475.5.3 NNBC 202: MRT-LOAD BEARING MASONRY................................................ 475.5.4 NNBC 203: 1994 - Guidelines For Earthquake Resistant Building Construction:Low Strength Masonry............................................................................................ 485.5.5 NNBC 204: 1994 - Guidelines For Earthquake Resistant Building Construction:Earthen Building (EB)............................................................................................. 495.5.6 NNBC 205: 1994 - MRT Reinforced Concrete Buildings without Masonry Infill 495.6 Review of NNBC 206: 2003 - Architectural Design Requirements ................................. 505.6.1 General .................................................................................................................... 505.6.2 High Rise Buildings ................................................................................................ 505.6.3 Other aspects ........................................................................................................... 505.7 Review of NNBC 207: 2003- Electrical Code..................................................................... 51
  4. 4. 5.8 Review of NNBC 208: 1994 - Plumbing and Sanitation ................................................... 515.8.1 Water Supply........................................................................................................... 515.8.2 Waste Water Disposal ............................................................................................. 515.8.3 Rain Water Disposal................................................................................................ 526 Conclusion............................................................................................................................. 537 Recommendation.................................................................................................................. 54Appendix-1: List of NNBC...................................................................................................... 57Appendix-2: Check list of activities for the study................................................................. 57Appendix-3: Interaction with Target Groups and National Workshop............................. 57Appendix-4: Review of NNBC: 000, 105 (State of Art, Seismic Design) ............................ 57Appendix-5: Review of NNBC 101, 102, 103, 104, 106, 108, 109 (Loads, Occupancy, SiteConsideration)..................................................................................................................... 57Appendix-6: Review of NNBC: 110, 111, 112, 113, 114, (Materials) .................................. 57Appendix-7: Review of NNBC: 107 (Fire Code)................................................................... 57Appendix-8: Review of NNBC: 201, 202, 203, 204 and 205 (MRT).................................... 57Appendix-9: Review of NNBC: 206 (Architectural Code)................................................... 57Appendix-10: Review of NNBC: 207 (Electrical Code)...................................................... 57Appendix-11: Review of NNBC: 208 (Water Supply and Sanitation).............................. 57Reference Materials ...................................................................................................................... 57
  5. 5. Abbreviations:ADRC Asian Disaster Reduction CenterADPC Asian Disaster Preparedness CenterASTM American Society for Testing of MaterialsAASHTO American Association of State Highway and Transport OfficialsAREMA American Railway Engineers and Maintenance-of-way AssociationACI 318 American Concrete InstituteAISC American Institute of Steel ConstructionAFPA American Forest and Paper AssociationsBPU Building Permit UnitBCPR Bureau of Crisis Prevention and RecoveryBSI British Standards InstitutionDDC District Development CommitteeDIN German StandardsDUDBC Department of Urban Development and Building ConstructionERRRPP Earthquake Risk Reduction and Recovery Preparedness ProgrammeESS Earthquake Safety SectionFSCN Fire Safety Code of Nepal (NNBC 107)HFA Hyugo Framework for Action (2005-2015)GON Government of NepalIRC Indian Road CongressISI Indian Standards InstitutionICC International Code CouncilIFC International Fire Code,IBC International Building CodeIRP International Recovery PlatformJSI Japanese Standard InstituteKMC Kathmandu Metropolitan CorporationKVTDC Kathmandu Valley Town Development CommitteeLSMC Lalitpur Sub-Metropolitan CityLSGA Local Self-Governance Act 1999LSGA Local Self Governance Act of Nepal, 1996 and Regulations 1997LSGR Local Self-Governance Regulations 1999LSM Low Strength MasonryNBCI National Building Code of India,NFPA National Fire Protection ActNNBC Nepal National Building CodeOBC Ontario Building CodePWD Public Works DirectivesSAARC South Asian Association for Regional CooperationUNDP United Nations Development ProgramVDC Village Development CommitteeUKBC UK Building Regulations 2000UDB Urban Development Byelaws of 2007, KVTDC, GON
  6. 6. Executive SummaryIntroductionThe assignment for preparation of the recommendation report for Updating the National BuildingCode of Nepal is entrusted to MULTI Disciplinary Consultants (P) Ltd in association with KDAssociates (P) Ltd. and Khwopa Engineering College through a contract agreement signedbetween the consultant and Earthquake Risk Reduction Recovery Preparedness Programme forNepal - UNDP/ERRRP-Project: NEP/07/010 (The Project) on December 15, 2008.The ProjectThe “Earthquake Risk Reduction and Recovery Preparedness Programme for South AsianRegion” is supported by the Government of Japan under a grant assistance for disaster preventionand disaster reconstruction contributed through the United Nations Development Programme(UNDP). The Project is designed to seek regional cooperation through sharing of knowledge andexperience in Disaster Management and to utilize the knowledge of recent EarthquakeEngineering.Objectives of the AssignmentThe objectives of the Assignment are to: a) review and recommend technical additions, alterationsand modifications, to be made in the current code, b) study, analysis and justify for update of theCode, c) review general practice of NNBC [implementation] in some municipalities (Kathmanduand Lalitpur), and d) study the effectiveness of implementation of NNBC in construction.Scope of WorksThe scope of works related to above mentioned Objectives is to: a) interact with majorstakeholders and experts, b) study linkages with current building bylaws, c) analyze the problemsfaced by Kathmandu and Lalitpur in implementation of NNBC, d) study technical issues raised bydesigners and professionals, e) compare NNBC with other codes, e) review the specificEarthquake Safety specifications, f) specify the technical details in the code to be updated foroverall revision of NNBC, g) specify the names of codes to be urgently updated, and h) preparefinal recommendation report for updating of NNBC.Interaction with the stakeholdersThe interaction with the stakeholders such as UNDP/ERRRP, NEA, SEEN, SCAEF, SONA,SEANEP, Licensed Designers of LSMC and KMC was carried out in four different meetings. Anational level workshop was organized on June 29, 2009 by ERRRP to discuss on the Draft FinalReport. The outcome of the interaction and comments obtained during the workshop coveredvarious aspects of NNBC and presented in Appendix-3 and summarized in Section 2.8. Thecomments and suggestions relevant to the current assignment had been incorporated in the reportwhereas certain queries which are not related to the Terms of Reference were included inAppendix-3 for consideration during the actual revision of the Codes.Apart from the details on the provisions of NNBC, the important aspects raised were: Confusion of Hierarchy and Priority of Acts, Bylaws, Codes, Standards, Directives,specifications, manuals, and References and Priority of the documents; Need for mechanism to implement the codes as part of the Building Bylaws Need for application of the code all over the country including VDC and small settlements Need of Unified Code and other codes as Architectural Code, Residential Code, HistoricalBuilding Code, High Rise Building Code, Fire Code, Plumbing Code, Construction SafetyCode, Retrofitting and Building Strengthening Code, Disabled Accessibility Code, MechanicalCode, Fuel and Gas Code, Environmental Code and Commentary on Codes.
  7. 7.  Anomalies of NNBC Frequency of Updates of Codes and Responsibilities Aesthetics, Change in Occupancy and Structural Safety, and annual Audit for compliancewith codes Use of MRT Regulation of Advertisement of construction materials Safety during handling and storage of materials Audit of Performance of Code implementing organisations, Ownership and Intellectual Property Right Education, Training, Qualification, Licensing of skilled labor.NNBC and NS SeriesThere are two sets of documents available which are known as Nepal National Building Code orNepal Standard. Actually, both of the series address the same issues. NNBC is presented asamendment to IS whereas NS are adaptation of IS or other standards into NS with relevantamendments.Normally, the codes and standards are revised and updated every 3 years. But for Nepalese case,this may not be pragmatic and frequency of updating may be adopted differently. TheInternational Code Council or other institutions dedicated for code development and updatingreview the codes at a regular interval, for example say 3 years. A regular process for recording ofoccurrence is carried out and forwarded to the standing committees for code updating. Nepal doesnot have a dedicated office for record of occurrence in relation to the need for updating of Codesand Standards.More detailed deliberations on specific codes are provided in Section 5 and Appendices.MRT not to be a part of NNBCStrong voices were noted for treating MRT as non-Code document since it is just an example ofdesign of various types of buildings and details following the provisions of NNBC. This documentis incomplete and do not include the requirements of other codes as Fire Code, Plumbing Code,Environmental Code etc. The quality assurance and construction complexities are not considered.Lalitpur Municipality from the very day of application of NNBC adopted certain changes in MRT.This document should be developed as model examples that fulfill the requirement of all codesand should be served as guide for proper design and shall not be a part of the Building Code.Implementation of NNBC by MunicipalitiesThe implementation of NNBC is made mandatory by issue of instructions by the Ministry of LocalDevelopment but the Building Act and Building Byelaws do not include NNBC provisions andhence remains ineffective and practically not applied in Building Permit Process. LalitpurMunicipality initiated the application of NNBC in the Building Permit Process in voluntarymanner since 2003. Kathmandu Municipality started implementation of NNBC only since 2007.The implementation of NNBC could not be initiated in other municipalities since the BuildingByelaws has not incorporated NNBC as part of it. It will be fundamental to include the NNBC andother relevant Family of Codes as described in Section 3 to be included in Building Bylaws.
  8. 8. Mandatory Application of Bylaws through out the countryThe Building Byelaws are by legislation applicable in the areas of jurisdiction of themunicipalities. Most of the areas in country side and rural areas are not covered by Building Actand Building Bylaws making the rural areas more vulnerable for Construction Safety. This loophole in Building Act has prompted many builders and owners to shift to VDC areas forconstruction for avoiding the need for obtaining Building Permits and avoiding application ofNNBC. This provision has defeated the purpose of NNBC in general.Implementation of Architectural Design Requirements and Planning GuidelinesThough the Architectural Design Requirements (NNBC 206:2003) had been introduced in 2003,the actual design had not been checked for compliance with this code and coordination withPlanning Guidelines and zoning plans been very week. The effect of coordination is clearly visiblein the haphazard development of the urban areas.Institutional Arrangements for Implementation of NNBCThere is no single institution responsible for all earthquake related matters in Nepal. Variousinstitutions and agencies are responsible for various earthquake related matters, and thecoordination among them is practically not provided. For this reason, the issues related to NNBCremain unattended and keeps waiting for a particular project to start. There is a dire need forestablishing Nepal Code Council that will address the development issues of Codes and theirimplementation.Code Structure, Nepal Standards and Family of CodesThere is a gross confusion about the hierarchy and priority of the documents in relation to Act,Bylaws, Codes (NNBC), Standards (NS), and Directives (PWD), Specifications, ManualsInstructions and administrative circulars. This aspect needs to be clarified and clear demarcationand definition is required.NNBC is a collection of individual codes. May be it would be more effective when compiled intoa unified code that takes into account the family of various other codes as Urban Planning Code,Fire code, Plumbing Code, Electrical Code, Construction Code, Construction Safety Code etc (Seelist in Section 3.6 Box 2) including provision for adoption of administrative procedures forimplementation.Criticism on NNBCA series of positive criticism on NNBC was spelt out during the interaction with the stakeholders.The major issues are highlighted in Section 3.5 and details are provided in Appendix-3. Mostimportant of all criticism is that since the code is presented as amendment to Indian Code, it haslost its value since there is no need to refer to an incomplete code when Indian Code is handy. Thedependency of other code has to be eliminated otherwise the international codes shall be adoptedas reference codes only. The Code requires technical and literature editing to eliminate errors andmisprints.Review of NNBC 000 to 208 and Comparison with other CodesThe review of NNBC has been carried out and a number of issues had been identified that wouldrequired to be considered while updating the Building Code. Comments and suggestions to everySection of the Code are provided in Appendices. Particular attention is drawn on major issuespointed out and few disasters that have occurred recently due to the lack of provisions in the code.They are:
  9. 9.  The provisions in the Codes have several ambiguous statements, Incomplete sentences,reference to the Indian Standard Codes of Practice, absence of the Commentary, designearthquake level is too un-conservative, Fire Hazard in rural settlements induced by poor planning of the settlements and inadequateconsideration of Fire Safety measures Changes in occupancy of buildings without confirming to Safety requirements, Electrical hazards associated with lack of adherence to Electrical Code Lack of coordination between Architectural Design Requirements and Planning and ZoningGuidelines Lack of Data base on Wind and Snow Loads Lack of Data base on Building permits granted that will highlight the use of NNBC.The updating of NNBC requires utilization of technological advancements and development ofinternational codes as IBC and Eurocode.Family of CodesApart from the NNBC series and NS serious, the need for a numerous other codes is identifiedwhich will be required to fulfill the purpose of achieving the safety of life and property andenhancing comfort of living. These additional codes are listed in Section 3.5.Environmental CodeThis Code is very specific and needs to be addressed while updating the Code. The important ofthis code is obvious since it affects the quality of life and its comfort. The code should introduce aseparate section for the Environmental Pollution Control covering following: Air Pollution (Indoor and Outdoor) Emission Control Sound Pollution Water Pollution Solar pollution Solid waste management Visual Pollution in Urban and rural Areas Landscaping Public Information for Safety of Life, Property and Peaceful LivingMandatory Rules of Thumb (MRT)The main objective of MRT is to provide ready-to-use dimensions and details for variousstructural and non-structural elements for up to three-storey reinforced concrete (RC), framed,ordinary residential buildings commonly being built by owner-builders in Nepal that include a)RCC framed with using brick infill walls, b) load bearing brick masonry, c) low strength ruralconstruction and earthen buildings.The details in MRT designs are provided without consideration of construction requirements forquality assurance (limitation of concrete placing from less than 1 m, allowing consolidation ofconcrete, preventing honey comb in concrete and smaller dia reinforcement (10mm and 12 mm infoundation and columns).The designs provided in MRT should serve as good illustrations of compliance to the requirementsof all codes (family of Codes) for the designers and owners. Hence, it is considered that MRTshould not be a part of the Code.
  10. 10. Recommendation for Update of Nepal NationalBuilding Code: Final Report1 Introduction1.1 GeneralThe current assignment of preparation of recommendation report for Updating the Nationalbuilding Code of Nepal is entrusted to MULTI Disciplinary Consultants (P) Ltd inassociation with KD Associates and Khwopa Engineering College through a contractagreement signed between the consultant and Earthquake Risk Reduction RecoveryPreparedness, Programme for Nepal - UNDP/ERRRP-Project: NEP/07/010 (The Project) onDecember 15, 2008.1.2 The ProjectThe Government of Japan has decided to provide a grant assistance for disaster preventionand disaster reconstruction, with a view to contributing to the “Earthquake Risk Reductionand Recovery Preparedness Programme for South Asian Region” through the UnitedNations Development Programme (UNDP).The UNDP/BCPR, the leading agency of the International Recovery Platform (IRP, Office:Kobe City, Hyogo Prefecture), and Japan have extended cooperation in this programme tofulfill the requirement of the Hyugo Framework for Action (HFA 2005-2015) to reduce thedegree of damage and quickly restore earthquake damage by promoting quake-proofcapacity of buildings, taking into consideration the strengthened capability in the field ofdisaster prevention of the South Asian Association for Regional Cooperation (SAARC) forthe South Asian region, including India, Nepal, Pakistan, Bangladesh and Bhutan.The Project is designed to seek regional cooperation through sharing of knowledge andexperience in best practice on Disaster Management and utilize the knowledge of recentEarthquake Engineering.1.3 The AssignmentThe assignment is related to preparation of recommendation report for updating of theNational Building Code of Nepal. The report will serve as base for updating of the BuildingCode by the Government.1.4 Objectives of the AssignmentThe objectives of the Assignment are:To review and recommend technical additions, alterations and modifications, to be made inthe current code To study, analysis and justify for update of the Code To review general practice of NNBC [implementation] in some municipalities (Kathmandu and Lalitpur) To study the effectiveness of implementation of NNBC in construction
  11. 11. 1.5 Scope of WorksThe scope of works related to above mentioned Objectives is: Discussion and interaction with ERRRP/DUDBC, stakeholder municipality and otherexperts Study linkages with current building bylaws prepared by DUDBC/Town DevelopmentCommittees Study and analyze the technical complications and problems faced by somemunicipalities (Kathmandu and Lalitpur) in the implementation process of NNBC Study Technical Issues raised by the designers and the professionals regarding therevision of the NNBC Study and Compare NNBC with other codes that are being practiced in Nepal such asIS Code and others Study other International Codes that are correlations with NNBC Study and review the specific Earthquake Safety specifications in building codes andguidelines already available in Nepal Specify the technical details in the code to be reviewed and updated for overall revisionof NNBC Specify the names of codes that have to be urgently updated Prepare final recommendation report for updating of NNBC Presentation of draft final report to ERRRP, UNDP,DUDBC, Municipalities and otherstakeholder organizations for comments and suggestions Preparation of Final Report1.6 MethodologyThe methodology adopted for meeting the requirement of above scope of works is: Collection and Study of data/information, documents on NNBC. The comprehensive listis given in Appendix-1; Collection and Study of data, information and documentation on building codeimplementation for government buildings by DUDBC Collection and Study of data, information and documentation on building codeimplementation in municipalities; Interaction with the users of the Codes as licensed designers of municipalities,professional consultants involved in the Earthquake engineering, municipal andgovernment authorities, professional organizations; Preparation of Recommendation for update of NNBC with detail information onamendments, revisions, alterations to be made.1.7 The Project Team, Inputs and responsibilitiesThe proposed team members are listed below in Table-1 along with the proposed taskassignmentTable-1: Proposed Team MembersSN Position Name Firm Input,MMTask Assignment1 ProjectDirectorMr. BLNyachhyonMulti 1 Administration, Quality ManagementCoordinationReview of Fire Code NNBC 107
  12. 12. SN Position Name Firm Input,MMTask Assignment2 TLStructuralEngineerDr. PremNathMaskeyMulti 1 Discussion and interactionReview of Building Codes 000, 105Compare NNBC with other codesStudy Codes correlations with NNBCSpecify the codes to be urgently updatedPrepare final recommendation report3 StructuralEngineerMr. PMPradhan* /Dr.GovindaLamichhaneKhec 1 Discussion and interactionStudy linkages with building bylawsAnalyze the problems faced by somemunicipalitiesReview NNBC 110, 111, 112, 113Specify details to be updated for overallrevision of NNBC4 CivilEngineerDr. RekhaShresthaMulti 1 Discussion and interactionStudy Issues raised by the designersReview NNBC 101, 102, 103, 104, 108,109, 114, 201, 202, 203, 204, 205Review Earthquake Safety specificationsin building codes and guidelines alreadyavailable in Nepal5 ArchitectPlannerDevendraNath GongalMulti Discussion and interactionReview NNBC 206Architectural Code6 SanitaryEngineerShankherAgrawal/Kul DeepTuladharKDA 1 Discussion and interactionReview NNBC 208System Protection and SafetyUninterrupted Supply7 ElectricalEngineerShambhooBahadurShresthaMulti 1 Discussion and interactionReview NNBC 207,Electrical Safety, System Protection, ,Uninterrupted Supply* Mr. PM Pradhan could not contribute to the study since he has resigned from Khopa Engineering College.1.8 Interaction with the Target GroupsThe Appendix -3 lists the Target Groups for interaction for brain storming on updating ofNNBC. The interaction sessions were carried out as follows: Dec 28, 2008 - Brief interaction with UNDP/ERRRP National Program Coordinator Feb 5, 2009 – Institutional Target Groups Feb 9, 2009 – Licensed Designers registered with Lalitpur Sub-Metropolitan City Feb 27, 2009 – Licensed Designers registered with Kathmandu Metropolitan CityThe notes on the Interaction programs are presented in Appendix-3.1.9 Major FindingsThe NNBC, described in 20 independent volumes, is mostly comprises of editing of certainterminology of IS Codes and as such requires intensive revision and updating. Practically,this updating cannot be done at this stage in view of availability of resources for review andupdating.
  13. 13. The revision and updating of NNBC are not done in a regular basis since there is nodedicated institution for this job. The revision and updating of Building Codes are verycomplex and cumbersome process that requires huge resources in terms of knowledgeaccumulation, institutional memory, time, research and development and statistics. The codeupdating assignment even for rich countries like USA and UK is very huge and requiresconsiderable investment. They have started standarisation at international level and todaymost of them use International Building Code. Those codes which are not included in theIBC are included by reference and used as a set of document agreed at international level.Each country or local governments are given rights to amend the parts which are not relevantto the local area and needs revision.There are no statistical records on the application of NNBC in recent construction of bothGovernment and Private Sectors. But it is evident that mostly used documents are MRT,which has good stories mentioned above and does not warrantee the safety of the Buildingdesign under it. With these facts in mind, it is required that MRT is taken away from thefamily of Building Codes but a separate standard design could be developed which could bereadily used by anybody without requiring to go through the Safety review procedures inMunicipalities.The provisions of NNBC are currently applicable within the Municipality boundaries andthere is no formal need to apply NNBC in rural areas. This weakness has to be changed andall buildings and infrastructures in the rural areas are also required to fulfill the requirementsof NNBC.It is recommended that as a priority MRT should be urgently discarded as part of the codeand replaced with standard design of typical buildings that complies with requirement of theFamily of Codes.The revision and updating of NNBC should replaced by adaptation of IBC with specificchanges of certain provisions that are relevant to the country and locality.A dedicated Institution as National Code Council shall be established urgently and entrustedthe task of development and implementation of NNBC and help to protect life and propertyfrom various risks of Natural and manmade disasters.The provision for implementation of NNBC shall be included in the Building bylaws whichgovern the external and internal design aspects of individual buildings and infrastructure andwarrant the least effect to the neighborhood.Though the building permit process according to Building Bylaws has granted certainpurpose to the buildings constructed in the urban areas, but there are considerable caseswhen the occupancy loads were changed without proper justification and without designrevision. They pose huge risks in terms of safety.Similarly, the case of high rise buildings needs to be looked very seriously and providespecific guidelines for comprehensive design.The Conclusion and recommendation are provided in Chapter 6 and 7.
  14. 14. 2 Current Practices2.1 National PolicyNepal is considered one of most vulnerable country for earthquakes. The recent earthquakes(1988 in Udayapur, Nepal) have prompted serious concerns for the earthquake safety ofinfrastructure. Following the major earthquake event in 1988, the Ministry of Housing andPhysical Planning undertook a policy initiative jointly with UNDP and UNCHS to addressneed for changes in current building design and construction methods. The UNDP / UNCHS(Habitat) Project and the Ministry undertook “Policy and Technical Support to Urban SectorProject” under which national housing survey, shelter sector training needs assessment, draftnational housing policy formulation, draft national building code preparation etc. wereundertaken. The ‘Building Act’ was adopted to facilitate the regulation of building design /construction practice in Nepal. The ‘Engineering Council Act’ was formulated to facilitateself regulation of the profession by professionals themselves. The Nepal National BuildingCode was prepared in 1994. At the same time The Bureau of Standards and Metrology haddeveloped the NNBC as Nepal Standards under various Standard Codes. But in the absenceof the Parliament the Codes and Standards remained unimplemented. The GujaratEarthquake of Jan 2001 prompted the Society of Consulting Architectural and EngineeringFirms (SCAEF, Nepal) initiated joint collaboration with NBSM for implementation ofNNBC and NS. The collaboration prompted to form the National Forum of EarthquakeSafety that facilitated the Declaration by Lalitpur Sub-Metropolitan City for implementationof NNBC and initiation of Master’s Degree Course in Earthquake Engineering by KhwopaEngineering College.2.2 Implementation of NNBC by MunicipalitiesLSMC is the First Leading Municipality in Nepal to implement NNBC in the BuildingPermit Process through a declaration on the occasion of Earthquake Safety Day celebrationon January 16, 2003 (2059 BS).The Implementation of NNBC was initially facilitated by the Technical Cell (Group ofMunicipal Engineers & Engineers from DUDBC, NSET, NFES, NEA) which worked for 6months prior to the establishment of the Earthquake Safety Section 27th November 2003(2060 BS).2.3 Building Permit Process in LSMCThe Building Permit Application in LSMC is processed in following steps (ref….): Registration by the Building Permit Unit of Municipality Checking for compliance with Building Bye-Laws Review the design by the Earthquake Safety Section (Technical Cell in initial stage) forcompliance with NNBC Presentation of the design by the Licensed Designer in a public forum organized byLSMC, ESS for sharing experience, knowledge, methodology of application of NNBC,confirmation of compliance to NNBC. This process was dropped at later stage and notcontinued any more. Building Permit is granted in two stages: Initial Permit for construction upto Plinth Level Final Permit after inspection of construction upto Plinth Level
  15. 15.  Inspection of Construction Progress by Municipality Staff Certification of Completion jointly by the Licensed Designer who supervised theconstruction and Building Permit Unit who inspected the construction.The general Building Permit process is provided in Section 2.4.2 below.2.4 Building Permit Process in KMCThe Building Permit process in KMC differs significantly. The compliance with NNBC forupto 3 storeys or 1000 sqft in area is reviewed by Building Permit Section and for Buildingsover 6 floors, it is checked by the National Building Code Implementation committee(NBCIC). The detailed procedure is described below. Kathmandu Metropolitan City (KMC)has started implementing building code-2060 from August 21, 2005, for the construction ofbuildings within the city. In October 2005 a National Building Code ImplementationCommittee was set up within KMC, it is comprised by six specialists who act on voluntarybasis.The general building permit process is as follows: Step 1: The Application for Building permit is checked for compliance with planningguideline as Guided Land Development, particularly for adequacy of accessibility; Step 2: For Buildings less than 3 storeys and less than 1000 Sqft, Computer checking byJunior Engineer for compliance with requirements of NNBC and Planning Bylaws;collection of revenue For Buildings more than 3 storeys and more than 1000 Sqft, checking by Engineer forcompliance with requirements of NNBC and Planning Bylaws; collection of revenue Step 3: Initial Registration and Computer Entry Step 4: Forward to Ward Office for Field Verification and Neighborhood Consent Step 5: Forward to Building Permit Section for Final Registration Step 6: Checking by Engineer and Issue of Building Permit for Construction upto DPCLevel Step 7: Checking of Construction upto DPC Level Step 8: Issue of Building Permit for Construction of Superstructure Step 9: Checking of Completion of Construction and Issue of Completion Certificate Step 10: Apply for water and sewerage service connections, Electricity andTelecommunication Step 11: The drinking and sewerage office sends their recommendation to the RoadsDepartment for permission to dig the road for the water and Sewerage connection. Step 12: The Department of Roads grants its permission to dig the road. Step 13: Inspection by water and sewage offices and Water and sewer connection iscarried out Step 14: Wiring Inspection before obtaining electrical power connection and telephoneconnection Step 15: Connection of Electrical Power Supply and Telephone connection2.5 Data and information on building code implementation2.5.1 Government Buildings by DUDBCDUDBC carries out implementation of certain government buildings through itsconstruction and Maintenance divisions. It is not known how far they comply with the
  16. 16. requirement of NNBC and who does certify the compliance since design and constructionsupervision documents and As-Built Drawings are not readily available.2.5.2 Practice in MunicipalitiesBuilding permit system started after the endorsement of ‘Building By-Laws in 1994(2050)’. Simply a set of Architectural drawings consisting of plans, four side elevations,section, location plan and site plan were required for submission and this was dealt by theDrawing Cell. This cell was also responsible for checking the compliance with otheraspects such as coverage, FAR, GLD, zoning etc. After the introduction of NNBC, a set ofstructural drawing was added to the list of requirements.From 2003, the requirement for architectural, structural design analysis, electrical etcdrawing sheets was introduced for SOA type of buildings (Class A) while the requirementwas limited to architectural and structural drawings for Class B type buildings and Class Ctype building does not require any structural design. In some cases where the area isdesignated as heritage conservation area, additional design for preservation of traditionalstyle and vernacular architecture is emphasized and permission from the Department ofArcheology is required.Initially, the building permit process included the technical committee for review ofdesigns by a panel of external experts comprising of the representatives from DUDBC,KMC, IOE, NSET and SCAEF. This process gained very essential lessons that benefitedthe crystallizing the Building Permit Process and was a learning stage for many LicensedDesigners and Building Owners. But soon, the review process felt lot of resistance sincethe Licensed Designers were unable to defend their designs and the process was felt as aburden to the Municipality. Certainly, a thorough and detailed scrutiny required excellentpreparation of the design and drawings.There are two certificate systems one is temporary which is given after DPC check, but thistemporary certificate is postponed now. The other is the Permanent completion certificateas obvious from the name is given after the completion check of the building construction.Now the number of structural drawing sheets has increased from one to three and pillarfrom 9”x 9” to 12”x12”. All engineered building for residential purpose which is morethan 1000sq. ft and 3 storeys require analysis report. For commercial buildings there is afurther requirement of soil test report and other drawings such as electrical, sanitation,plumbing.NNBC was enforced through the endorsement of Building Act 1999, but formally it wasimplemented only in 2003 because the Building Bylaws did not make any reference to theimplementation requirements of the Building Code. NNBC has categorized buildings intofour categories namely type A, B, C and D.2.6 Institutional Arrangements for Implementation of NNBCThere is no single institution responsible for all earthquake related matters in Nepal. Thefollowing agencies are responsible for various earthquake related matters: Department of Mines and Geology is responsible for earthquake instrumentationnetwork in the country and preparation of the seismic zone map of the country.
  17. 17.  National Bureau of Standards and Metrology is responsible for the certification ofstandards and constituents of codes and guidelines on various public works includingearthquake matters. National Building Council is envisaged as an apex body to deal with the creation andupdating of the National Building Code of Nepal. Department of Urban Planning and Housing is responsible for the creation andimplementation of Nepal National Building Codes including earthquake matters. Kathmandu Valley Town Development Committees are responsible for formulation ofFormulation of urban development plans, planning and building byelaws. Local bodies (VDCs, DDCs and Municipalities) are responsible for formulation and/oradoption of bylaws, codes, norms, regulations and enforcing / policing theirimplementation in the areas of their jurisdiction. Professional Societies as NEA, SCAEF, SONA, SEANEP, SEEN, ESI, NSET and otherNon-Government Organisations are responsible for information dissemination,awareness campaigns, upgrading the knowledge and skill of their members to complywith these codes in their professional practice and occasionally provide training. Donor agencies involved in the area of earthquake safety include UNDP, UNCHS,UNESCO and JICA.There is no dedicated institutional arrangement for dealing with the Earthquake Safetymatters, follow up and updating of NNBC, for expert advice, and pursuance for applicationof NNBC by local Governments including Municipalities and VDCs.2.7 Jurisdiction of Application of NNBCThe Local Self-Government Act Part 2-VDC Clause 28 (f) (2) has made provision of thecriteria for construction of Buildings and Infrastructure. LSGA Part 3-Municipality Clause96 (b) (6) has made provision for approval of Building Construction. These provisions couldbe rationally utilized for application of NNBC in VDC and Municipality areas effectively.More specific and elaborate guidelines may be required.Building Act 2055 (amendment 1998) has given authority to all municipalities to implementthe NNBC for providing Building Permits. However, the Act do not specify a particularorganization that is authorized to follow up and monitor the compliance to NNBC by theMunicipalities.2.8 Subscribed methods (PWD) of Seismic design considerationPWD Part II Chapter has provided certain guideline for Earthquake Consideration inInfrastructure Project Sector. The guidelines for earthquake considerations apply to thefollowing categories of structures: All buildings having a plinth area greater than 20 m2 or height ranging from 5 m to 90m. All masonry and concrete walls having a height of greater than 1.5 m. All elevated water tanks and silos with capacity up to 200 m3. All public buildings having general public access. All civil engineering structures such as bridges, dams, earth structures, silos, water tanks,chimneys etc. All towers and electric or telecom or radio pylons.
  18. 18. The requirements of these guidelines shall be followed at minimum. The designer ishowever free to exercise more stringent procedures if considered necessary considering themerit of the case.3 Consideration of Problems and Issues of NNBC Application andConstructionThe problems and issues related to the application of NNBC and construction quality arelargely discussed in various interaction programs with major stakeholders and brief notes onthe discussion points are described in Appendix-3. These issues are briefly highlightedherewith:3.1 The CodesA code is a set of technical specification and standards that control major details of analysis,design, construction and equipment. The purpose of the code is to produce safe andeconomic design so that people are protected from poor and inadequate design andconstruction.Two types of codes exist. One type of code is called “Structural Code” and is written byStructural Engineers and other specialists who are concerned with a particular class ofstructures (e.g., buildings, bridges, nuclear plants) or who are interested in proper use ofmaterials (Steel, Aluminum, Reinforced Concrete, Plastics or Wood). Typically, structuralcodes specify design loads, allowable stresses of various parts of structures, designassumptions and requirements of material. Examples of Codes frequently used by structuralengineers include following: AASHTO – Standard specification of Highway Bridges AREMA- Manual for Railway Engineering ACI 318 – Building Code requirement of reinforced concrete AISC – Manual for Steel Construction AFPA- National design Specification for Wood ConstructionThe second type of code, called Building Code, is established to cover construction in agiven region (a state, city or country). A building code contains provisions pertaining toarchitectural, structural, mechanical, electrical, requirements. The objective of a buildingcode is toprotect the public by accounting for the influence of the local conditions onconstruction. Those conditions of particular concern to the structural engineers cover suchtopics as soil conditions, live loads, wind pressure, snow load, and earthquake forces. Todaymany building codes adopt the provisions of Standard minimum design loads for Buildingsprepared by ASCE or more recent International Building Code by ICC.As new systems evolve, as new materials or new technology becomes available, or repeatedfailures of accepted design occur, the cont3ent of codes are revised and updated. In recentyears, a large volume of research on structural behavior and materials has resulted infrequent changes in both types of codes. For example, the ACI committee issues annualaddendum and produces revised codes every 6 years.Most codes make revision to depart from the provisions in the standard provision if thedesign can prove by the test or analytical studies that such changes can produce a safedesign.
  19. 19. 3.2 Hierarchy of Act, Bylaws, Codes and Standards, and ReferencesThere is a gross confusion about the hierarchy and priority of the documents in relation toAct, Bylaws, Codes (NNBC), Standards (NS), and Directives (PWD), Specifications,Manuals Instructions and administrative circulars. This aspect needs to be clarified and cleardemarcation and definition is required.The reference to other international codes as IS, IRC, JSI, DIN, ASTM, Eurocode and othersshall be provided.3.3 Building bylawsThe building byelaws of municipalities do not include several codes which are consideredvery essential for enhancing safety and quality of Life. The safety of Neighborhoodbuildings such as supermarkets, high rise buildings, hospitals, schools, institutional building,water towers, electrical towers, communication towers etc requires special treatment anddeserves specific consideration. The existing bylaws do not deal with hazardous buildings asabandoned and dangerous houses. The Building Permits process shall include all codesrelevant to the safety of buildings and infrastructure. Apart from this, the bylaws shallinclude provisions for innovativeness in planning and design.3.4 Code Structure and Nepal StandardsThere are two sets of similar documents: One published by DUDBC under NNBC 000 toNNBC 208, and another set published by NBSM under NS series. NNBC is basically refersto IS with corrections made for internalizing with Nepal Requirements. So, NNBC is adependent code and requires intensive reference with IS. In the other hand, NS has adaptedthe NNBC provisions and replaced the references of NNBC with relevant clauses adaptedfrom respective international codes. This duplication of NNBC and NS has createdconfusion among the users of Nepal Codes. NNBC requires to be made more users friendly,warrantee safety compared to other codes and build confidence among the professionals andcommunity as a whole.3.5 Need for Unified CodeNNBC is a collection of individual codes. May be it would be more effective when compiledinto a unified code including provision for adoption of administrative procedures forimplementation.3.6 Criticism of NNBCSeveral experts and professionals have reported that NNBC contains several anomalieswhich make it unreliable and confidence on it could not be developed. These factors arerelated to: The Safety factors, Importance factors, Response spectra, Worse case of load combination Low Load factors, Load reduction provision, Load distribution of non-orthogonal plan Lateral earth pressure in basement Load distribution for high rise and low rise Time period < 0.1 N
  20. 20.  Design Parameters as:- Settlement, deformation, strength, crack opening- Static and dynamic analysis- Retrofitting of existing buildings by laws / codes- Repair and maintenance of old existing buildings/ code- Disaster mitigation – building stock inventory3.7 Family of CodesThe International Code Council has adopteda series of codes that comprehensivelyprovide safety of life and property, andenhance the quality and comfort of thepeople. This aspect has not been covered byBuilding Act of Nepal and Byelaws of anymunicipalities and the building codesprepared have limited provisions. The list ofInternational Codes used is listed in Box-2.These codes are part of Building By-Lawsand required to be followed as the minimum.3.8 Frequency of UpdateThe Bylaws, codes and Standards requiredto be updated within a certain period inorder to address the dynamic technologicaldevelopment and requirement of theconsumers.3.9 Commentary on Codes and StandardsInclusion of Commentary on Codes andStandards is most important since itdevelops the confidence of the users, andprovides evidence of authenticity. Thecommentary shall be included in the samecode and standard where it is required to beprovided.3.10 Conservation of Historic Building, Aesthetics, Planning CodesNNBC includes a code on ArchitecturalDesign Requirement (NNBS 206:2003),but the important aspects of urban areas asconservationof historic buildings, aesthetics and context of urban areas affecting the neighborhood safetyare missing which has a huge toll on the urban safety. The building permit process in thevicinity of historic buildings and in the World Heritage Sites or Preservation areas are notsubject to the requirements of Department of Archeology which is the governing body forconservation of buildings and heritage sites.Box-2: List of International Codes in Use1. Building Code *,2. Residential Code,3. Mechanical Code,4. Plumbing Code *,5. Fuel Gas Code,6. Fire Code *,7. Property Maintenance Code,8. Private Sewage Disposal Code,9. Electrical Code10. Energy Conservation Code,11. Existing Building Code,12. Utility Codes (Lifts and Escalators, Lighting andventilation, Prefabrication and System buildings,Acoustics, Noise control, Air Conditioning andHeating, Communication and Networking)13. Urban Wild land Interface Code,14. Performance Code,15. Planning and Zoning Code16. Code and Commentary17. Elevator Safety Construction Code18. Historical Building and Conservation Code19. Reference Standards Code20. Disabled Accessibility Guidebook21. National Green Building Standard22. Nonstructural elements code23. Code for Special Buildings as high risebuildings, water towers, bridges.24. Construction Safety25. Environmental Codes (Indoor and OutdoorAmbience)26. Retrofitting and Building Strengthening Code* Codes included in NNBC
  21. 21. 3.11 Relationship between Aesthetics and Structural SafetyIn several cases, the architectural shape and size artificially dictate the type of structures tobe used which violates the structurally safety provisions. The codes shall make a distinctionof the relationship between the architectural shape and structural safety requirement.Similarly, the building shape and configuration have effect on ductility of the building andoverall safety against Earthquake Hazard.3.12 Change in OccupancyThere are several occasions of change of occupancy category of the buildings that threatenthe safety of life and property. Recently, several of hotel buildings have changed occupancyto supermarkets and office buildings. The residential buildings are easily used foraccommodating lower class schools, warehouses, and offices. Such changes in occupancyrequired to be monitored and shall be governed by the provisions in Building Bylaws andcodes.3.13 High Rise BuildingsThe requirement of high rise buildings in terms of overall safety is different than that of lowrise buildings. The quality of materials and reliability of technology is much stringent andoperation and maintenance of the service require higher degree for reliability. Thisrequirement should be covered by NNBC.3.14 Detailing of JointsThe use of facede materials as granite, glass panels and traditional decorative bricks (DachiApa) requires inclusion of detailing of joints with main structure in order to warrantee thesafety during Earthquake. The details of connection of infill walls, parapet walls, sunshadesand main frames shall be considered.3.15 Quality Monitoring and Advertisement MarketThe current practice of quality assurance of materials and their use in construction is gettingin mess. There is no uniform method of quality monitoring exits except for the voluntaryapplication of quality standards at the large scale project level. The materials in the marketare dominated by commercial advertisement irrespective of applicability of the products tothe specific job and requirement of quality parameters. More the advertisement materials aremisleading to the consumers since the information provided in the advertisements are notcorrect or not applicable to the situation at the particular job. The business communityexploits the consumers for their lack of knowledge understanding and ignorance, and lack ofinstitutional approach towards monitoring the advertisement materials.3.16 Supervision of Construction WorksThis is one of the weakest parts of implementation of NNBC and NS. The qualification ofHuman resources being engaged in supervision and quality of materials and equipmentrequired to be addressed.
  22. 22. 3.17 Building Material Handling, storage and useThe Safety of public and labor during material handling, storage and use is not taken care of.Use and handling of hazardous materials as fuel and electricity and other inflammablematerials shall be considered with special care. The sales of cement, steel, brick and sand atpublic places are harmful to health.3.18 Specification of other Materials not mentioned in NNBCThere are several other building materials that are commonly used in the market whereasthese materials are not included in the Codes or Standards. There should be a mechanismwhere these new materials and technology could be permitted for use under the codeprovisions.3.19 Mechanism for addressing Technical issues and data bankThe mechanism for addressing technical issues on provision of codes, standards,specification and construction technology is lacking. Similarly, data on experts onEarthquake Safety and Building Code matters are not consolidated. A data bank on Codeand Earthquake Safety matters will be extremely helpful including the development of alibrary for collection of important reports and research works.3.20 Participation of masons, stakeholders, ownersThe participation of stakeholders directly involved in the project as masons, owners andother stakeholders in code making and updating is lacking.3.21 Info dissemination and InteractionsInformation dissemination on code related issues are not adequately made. The informationrarely reaches the concerned stakeholders as professional societies and entities. Theinformation on the codes and standards shall be discussed with the stakeholders at length formaking the codes more effective and popular.3.22 Construction SafetyThe Construction safety is dealt in NNBC 114: 1994. However, it is limited to certain itemsand major safety issues as responsibility and accountability of safety is not considered. Atthe same time several items as formwork, reinforcement, concreting, equipment operationand many more are not included.3.23 Ownership of Design and Intellectual Property rightsThe ownership of the designer over the design and intellectual property right of the designer,the contractor and major technology suppliers is not covered by NNBC. This will be animportant aspect to be included in the Building Code.
  23. 23. 3.24 EducationThe education in Engineering Colleges is based on course books and seldom referred to theNNBC or other codes and remained more academic and not pragmatic. The use of codeprovisions shall b encouraged for practical classes. The colleges are the best places forbuilding awareness on need for use of codes and standards.3.25 Capacity of personnel, qualificationThe qualification of the administrators of the codes at municipality level is another issue.The application of codes is ignored since there is lack of adequate human resources withknowledge of Codes. Equally, important is the qualification of the designers who arebasically responsible for compliance with the codes. This qualification requirement shall beapplicable to the contractor’s staff as well.3.26 Licensing of Skill LaborLicensing of Skilled construction workers, inspectors, supervisors and professionals shouldbe adopted with provision of appropriate training addressing the requirement of qualitymonitoring.4 Implementation of Codes and StandardsThe current practice of implementation of codes and standards is very poor. Particularly, thisis correct since there is no institution that is responsible for monitoring the implementation ofthe Codes and the roles and responsibilities of various entities involved are not defined incontext of application of NNBC and NS. Appropriate Institutional Arrangement forcontinuity of follow up for upgrading NNBC will be required. NNBC has certain provisionof Water Supply, Sanitation and Plumbing (NNBC208:2003), Electrical Safety (NNBC207:2003), and Fire Code (NNBC 107:1994) but these codes are seldom used for grantingthe Building Permit.4.1 Water Supply and SanitationThere is no code related to water supply.4.2 Electrical CodeElectrical Safety Code (NNBC 207:2003) provides certain guideline for electrical details tobe made. However the need for detailed electrical diagram including wiring details is notstrongly spelt out and monitoring of safety shall be considered. Nepal Electricity Authoritymakes certain verification of the house wiring prior to providing connection to the citysupply.4.3 Fire Safety CodeThe Fire Safety Code as provided by (NNBC 107:1994) is limited in application of certainprovisions as fire alarm and other appurtenances. The requirement for design considerationand selection of building material based on Fire Grading of the Building category is notincluded.
  24. 24. 4.4 Use of NNBC 205: MRTThe municipality licensed designers widely use these codes for all construction beyond thelimit of MRT for building of larger sizes as well.Equally, MRT is extensively used for rural construction. It shall be said that this document isa very useful one but need to be very cautious since the designers in urban areas particularlyare misusing this document and threatening the safety. The minimum size of column of9”x9” recommended in NNBC is considered inappropriate for construction and LSMC isadapting 9”x12”, and changed the concrete grade from M15 to M20.It was referred that while better examples of standard typical designs to be made availablefor replication where permitted, MRT itself should not be a part of the Bylaws, Codes andStandards.5 Review of NNBC5.1 Review of NBC 000: 1994 State-Of-The Art Design And NBC 105: 1994Seismic Design Of Buildings In Nepal5.1.1 GeneralSeismic design of buildings constitutes the principal component of the building codes. Thepurpose is to reduce or mitigate the damage due to future earthquakes. It has been wellrecognized that the single most important development in reducing earthquake losses in theworld has been the incorporation of seismic design provisions into the building codes. Theseismic codes of various countries are in a state of continuous evolution in research andchanges in construction practice.The history of building code and hence the seismic design of buildings in Nepal is attender age compared to the same of other countries. The need for national building code inNepal was first strongly felt following the substantial loss and damage due to Udayapurearthquake of 1988. The preparation of the building code was initiated in early nineties andpublished officially only in 1994. The general response to the code has been lukewarmsince its inception, and is in a state of model building code rather than a national buildingcode in terms of legal status.Substantial advance have been achieved in the knowledge related to seismic resistantdesign of buildings and structures during the past 15 years since the publication of theNational Building Code of Nepal. Changes in seismic design provisions in seismic codesof different countries from 1994 to the present date are many and far reaching in theirimpact. Part of the reasons for such changes has been to incorporate the lessons learnedfrom the devastating large earthquakes. Inclusion of the lessons learnt from 1994Northridge and the 1995 Kobe earthquakes have been the major highlights of 1997 editionof Uniform Building Code with a considerable change in 1994 edition of UBC. Since thenthe large earthquakes of Gujarat (2001 January), Sumatra-Andaman (2004 December),Kashmir-Kohistan (2005 October) and China (2007) have resulted into devastating lossand damage, imparting the new lessons to be incorporated in the next future seismic codes.The lessons learnt from the past earthquakes, rapid development in the technology and
  25. 25. researches in the area of Earthquake Engineering have resulted into sophisticated seismiccodes in developed countries. The recent editions of National Earthquake HazardsReduction Program (NEHRP) Provisions following the custom of updating in a cycle ofthree years substantiate the fact. The recommended provisions incorporated in ‘TheNEHRP Recommended Provisions for Seismic Regulations for New Buildings’ haveincreasingly been adopted in recent times by model codes and standards. If in UnitedStates, there is a custom of revising the codes every three years, it may be not that easy incase of developing countries like Nepal. The revised edition of the Indian standard Criteriafor earthquake resistant design of structures IS 1893(Part 1) 2002 came into light replacingIS 1893: 1984 only after a period of 18 years. However, it should be recognized that theupdating of design documents like the codes is a dynamic process, and shall bematerialized as soon as possible to further reduce and mitigate the possible losses in futureearthquakes. In view of this, it is urgently needed that the present code on seismic designof buildings in Nepal is carefully reviewed with an objective of removing any deficiencies,errors or scope for misinterpretation. Moreover, development of commentaries orexplanatory handbook on the code to explain the provisions with solved examples is ofutmost importance to solicit a favorable response from users.5.1.2 NNBC 000: 1994 Requirements For State-Of-The Art DesignNNBC 000: 1994 basically describes the preface of the building code preparation andphilosophy behind the need for seismic design of buildings in Nepal. It describes andadvocates for, in general, four different levels of sophistication of design and construction,namely, International state-of-art, Professionally engineered structures, Buildings of restrictedsize designed to simple rules-of-thumb, and Remote rural buildings where control isimpractical. Accordingly, the NNBC 000: 1984 contains four separate parts describing therequirements for each category of the design sophistication. The categorization of the designand construction is highly influenced by the typology of buildings prevalent then in Nepal andappears highly overwhelmed by the fact that the first ever building code should be generous toaccommodate the unsophisticated and un-engineered design. It implies the poor status ofdesign capability and exposure to building codes and standards. It calls for a need to not onlyto revise regularly but also ascertains that the provisions are drafts standards for adoption byNBSM. The content of NNBC 000: 1994 could have been a set of good guidelinesincorporated in local building regulations or byelaws. Since a national building code alsorepresents the status and sophistication of design and construction embracing latest researchand technological developments, it should not only emphasize but also concentrate only on theInternational state-of-art.A building code is a set of rules that specify the minimum acceptable level of safety forbuildings and other constructed objects. The main purpose of the building code is to protectpublic health, safety and general welfare as they relate to the construction and occupancy ofbuildings and other structures. The Building Code becomes the law of a particularjurisdiction when formally enacted by the appropriate authority. Generally the codes aremeant for regulating building activity which may be recommendatory or mandatorydepending upon the authorities issuing these. Compliance to the building code ismandatory when it is covered in Building Byelaws, Regulations, Acts, Rules, etc. issuedby the National Government and various regional or local authorities.Building Codes are generally intended to be applied by architects and engineers, but arealso used for various purposes by safety inspectors, environmental scientists, real estatedevelopers, contractors, manufacturers of building products and materials, insurancecompanies, facility managers, disaster management personals, and others.
  26. 26. The practice of developing, approving, and enforcing Building Codes is different from onecountry to another. In some nations Building Codes are developed by the governmentalagencies or semi-governmental standards organizations and then enforced across thecountry by the national government. Such codes are the National Building Codes, and theyenjoy a mandatory nation-wide application. In the countries, where the power of regulatingconstruction is vested in local authorities, a system of Model Building Codes is used.Model Building Codes have no legal status unless adopted or adapted by an authorityhaving jurisdiction. In some countries, each municipality and urban development authorityhas its own building code, which is mandatory for all construction within their jurisdiction.Such buildings codes are variants of a National Building Code, which serves as modelcode proving guidelines for regulating construction activity. The degree to which nationalbuilding codes and standards are enforced by law varies from country to country, as stated inthe Foreword of the Code, however it was intended that its implementation be enforcedthrough the Parliamentary Bill Act and concerned, local authority by-laws. In the abovescenario, it has become very important to establish the status of the building code. It is to benoted that Building Byelaws, in relation with Building Codes, are mandatory rules andguidelines for construction activities, issued normally by governmental agencies orauthorities with jurisdiction. Byelaws reflect the legal status of the document, and areregulatory in nature. National Building Code or Model Building Code may be included asan essential part of Building Byelaws; however, building codes may not contain thebyelaws. In view of this the philosophy of various levels of requirements depending uponthe design sophistication are more relevant to the byelaws to be enforced by the central orlocal authorities. It is always preferable to maintain the distinct boundaries betweenexisting building byelaws/building regulations and building codes to avoid the confusion.The sanctity of the building code, different from building byelaws and buildingregulations, and in its turn, the seismic design of buildings shall be retained by focusing onthe international state-of-art.It is important to understand the expressed or implied purpose of a particular designdocument in order to fully appreciate its provisions. Although the basic purpose of anyseismic code is to protect life, the way that this purpose as well as any additional purposes,presented can provide additional insight into the reasons for the presence of specificprovisions in the body of the document and its intended audience. The document shall befree, as far as possible, of ambiguous or confusing statements or provisions. The followingparagraph describes some of issues to be resolved under NNBC 000: 1994: The background of the development of the building code and the philosophy of seismicdesign could be reasonably incorporated in the introductory part of Seismic Design ofBuildings or even in that of National Building Code itself. The requirements for theProfessionally engineered structures (Part II), Buildings of restricted size designed tosimple rules-of-thumb (Part III), and Remote rural buildings where control is impractical(Part III) along with minimum design requirements based on the flow chart (Figure 1) shallbe left out for building regulations or building byelaws. The requirements for theInternational state-of-art is the main part, based on which the Seismic Design ofBuildings evolves. The need for a separate code on the remaining issues is notjustifiable. Labeling the Building Code or part of it as draft standards belies the purpose of thedocument, and weakens the position of the code executing agencies in theenforcement of the building code.
  27. 27.  Ambiguous statements shall be removed unless a necessary clarification is provided toavoid the scope for misinterpretation. The return periods mentioned for the onset ofdamage of a typical building and for the strength of building as 50 years and 300 yearsrespectively, in 1.2 Seismic Design under Part 1, need a clarification or rephrasing. Incomplete sentences in the document of importance shall be avoided. The sentencestarting with “The basic philosophy for…” and ending in blanks, in 1.2 Seismic Designunder Part 1, fails to express the principal objective of the seismic design. The language and the format of clauses and provisions in a building code deserve aformal/legal style rather than those of a technical report. The paragraphs following thesubheading 1.3 Other Loads under Part 1 appear like parts of a report with a littleregard for other Nepalese Standards. Mere referring the Indian Standard Codes of Practice for design in materials likeconcrete, steel and masonry does not serve the purpose of popular use and enforcementof Nepal National Building Code. IS 456: 1978 Indian Standard Code of Practice forPlain and Reinforced Concrete has been revised into the Fifth revision IS 456: 2000Indian Standard Code of Practice for Plain and Reinforced Concrete. Similarly thedetailing requirements included in IS 4326: 1993 Indian Standard Code of Practice forEarthquake Resistant Design and Construction of Buildings have been modified andincorporated in a separate detailing code IS 13920: 1993 Indian Standard Code ofPractice for Ductile Detailing of Reinforced Concrete Structures subjected to SeismicForces. Since the present building code of Nepal is not explicit about which IndianStandard Codes, referred ones or revised ones, to be adopted, the designers along withother stake holders obviously will be in dilemma. Due reference to Nepalese Standards without using the adjective – draft, and withoutthe background of their development, is most preferable. The Nepalese Standards, suchas for Wind Loads (NNBC 104: 1994), Steel Design (NNBC 111: 1994), Un-reinforced Masonry (NNBC 109: 1994) and others shall be reviewed and improved, nomatter assistance from which international codes or publications has been derived, sothat these could be treated with respect as Nepal’s own Standards and essentialcomponents of the National Building Code. Due weightage needs to be given to international coordination among the standards andpractices prevailing in different countries in addition to relating it to the practices in thefield in Nepal.5.1.3 NNBC 105: 1994 Seismic Design Of Buildings In NepalBackground and purpose of the codeThe important information regarding the preparation of the code including its history ofdevelopment, need of the document development/improvement and the purpose of seismicdesign shall be described under Foreword. Due credit shall be given to the documents andcodes, which have been used and referred in the development of the code.The present form of Foreword needs to be enhanced with changes in terms of content anddescription. The name of sub-heading - design procedure and its content stating as theminimum design requirements for the seismic design of structures do not match; referring justto the section under the scope does not say any thing about the design procedure nor about theminimum requirements.
  28. 28. The special emphasis on the need for application of the code in conjunction with IS 4326 –1993, under sub-heading – Related Codes is not appreciable for two reasons. Firstly, the statusof IS 4326 – 1993 in India has been changed with most of the contents being separatelytransferred into newly developed codes. The statement in the para implies that NNBC 105:1994 can not be used without referring IS 4326 – 1993. In principle, emphasis should be on theneed of developing such basic standards or codes. Alternatively, the relevant provisions shallbe incorporated, separately as clauses, in the seismic design code itself. Naming recent editionsof IS 4326 – 1993 or other relevant national and international codes or documents as referencematerials will be more appreciated. Moreover, details of the Standards, preferably developedfor Nepal, which are necessary adjuncts to the Seismic Design of Buildings in Nepal shall belisted elsewhere in the code.The absence of the Commentary, forming an accompanying volume to the code, makes itdifficult to substantiate the requirement of using the code in association with the Commentaryas given under sub – heading- Commentary.ScopeThe requirements presented under the section of scope of the present code sound conservative.Instead, the scope of the code should be general and broad in terms of seismic load assessmenton various structures and seismic resistant design of buildings. The basic provisions shall beapplicable to buildings, elevated structures, industrial structures, dams, bridges and otherstructures. The scope may not include the construction features of those buildings for whichseparate standards will have to address.TerminologyThe terms used in the seismic design and their definitions given in the present code should beextended. Since the code is the sole principal document for earthquake resistant design ofbuildings it will be preferable to include basic terms and their definitions related withEarthquake Engineering in general to shed light on basic seismological aspects, as well asEarthquake Engineering related with buildings. Basic terms related with damping, modes,spectra, PGA, importance factor, intensity and magnitude of earthquake, liquefaction,maximum considered earthquake, normal modes and modal characteristics, seismic weight,zone factor and others related with basic Earthquake Engineering shall be included. It is alsonecessary to incorporate more terms related with building such as base, center of mass andrigidity, design eccentricity, base shear, bracing systems, lateral load resisting elements,principal axes, P- effect, storey drift, storey shear, soft storey and others.SymbolsThe symbols used in the present code may be retained with the extension or revision as themethod improved or altered. However, some terms used in the symbols may be changed, forexample, fundamental time period is more suitable than translational period Ti. There isperhaps a typographical error in meaning the symbol Fp –design seismic force for elementsand components designed in accordance with 8.General Principles of DesignThe general principles described under the present section 3 of the code could be elaboratedwith the important features of seismicity and basic assumptions of seismic design.
  29. 29. It is necessary to include the general principle adopted regarding the ground motion, itsfeatures in relation with the earthquake source characterizations including the sizes of theearthquake.It will be favorable to describe the seismic design approach adopted in the code. The generallyaccepted principle of seismic resistant design of buildings is that structures should be able towithstand minor earthquakes without damage, withstand moderate earthquakes withoutstructural damage but with some non-structural damage, and withstand major earthquakeswithout collapse but with some structural as well as non-structural damage. These widelyquoted objectives, however, are unstated in many codes including the current NNBC 105:1994. Instead, the principal objectives are stated, for example, the Uniform Building CodeUBC 1997 states an overall objective of safeguarding life or limb, property and public welfare.Although the definitions of minor, moderate and major earthquakes are variable, theygenerally relate to the life of the structure, and the consequences of failure. The majorearthquake level defined in most of the codes of the world has a recurrence interval of 475years, which corresponds to a 10% probability of exceedence in 50 years that is commonlyaccepted to be the expected life of a building. The corresponding service level earthquake for atypical building would have a recurrence interval of 10 years and a 99.3% probability of beingexceeded in 50 years.There is also a need to mention about the design approach in relation with consideration oflateral force in each of the two orthogonal horizontal directions, and approach regardingconsideration of earthquake load in vertical direction. It shall also include the approach andcorresponding provision regarding simultaneous occurrence of wind or flood, soil-structuralinteraction and change in usage of the building.Design Methods and Load CombinationsThere must be a valid logical reason for need of Limit State Method of design for reinforcedconcrete design and recommending Working Stress Method for other structural materials. Atthis juncture of improvement, it will be preferable to explore the design methods available andrecommended in other codes and adopt the design method most appropriate for the country. Ingeneral, most of the countries have adopted Limit State Method or Strength Method replacingWorking Stress Method for Concrete as well as Steel, the two principle structural materials.The provision regarding the increase in allowable soil bearing pressure by up to 50 percentwhen earthquake forces are considered along with other design forces according to 4.3 of thepresent code may be too un-conservative and ambiguous in application. Elaboration of theclause is required about in what condition 50% increase can be considered, and in whatcondition lower values, which are to be mentioned, of increment can be considered. IS 1893(Part 1) : 2002 recommends the increase in allowable soil bearing pressure from 25 to 50%depending upon the soil type (hard, medium or soft ) and the type of foundations (piles, raft,combined, isolated and well).The design load combinations included in the present code for Working Stress Method as wellas for Limit State Method seriously require reworking. It is well recognized that the loadfactors, recommended are based on the reliability levels assumed in the structures. Forexample, it appears too un-conservative to have load factor for dead load as 1 and for live load1.3 in case of Nepal. The uncertainties due to non-uniformity of materials, workmanship,quality control seem to be ignored in the load factor for dead load. The uncertainties inoverloading is covered by maximum 1.3 may not be practical in the condition of Nepal. IS 456: 2000, for example, considers 1.5 for both the dead load and the live load. Similarly themaximum load factor value for seismic load considered is just 1.25, both in combination with
  30. 30. 0.9 times dead load, as well as in combination with dead load and 1.3 times live load. Thevalue of 1.25 is too low in view of the large uncertainties involved in assessment of theseismic load. Furthermore, the recommendation for adoption of partial safety factors as perTable 12 of NNBC 110: 1994 contradicts the provision of 4.5 of Seismic Design Code.Method of Seismic DesignThe present seismic code recommends two methods of earthquake analysis, namely, SeismicCoefficient Method and Modal Response Spectrum Method.The bulk of seismic resistant buildings are designed using equivalent static lateral forces torepresent the effects of ground motion due to earthquake on buildings. It is from theassumption that equivalent static forces can be used to represent the effects of an earthquakeby producing the same structural displacements as the peak earthquake displacement response.The application of this method is limited to reasonably regular structures. The present coderestricts the use of this method for structures up to 40 m height, and should also mention thecondition of regularity.The dynamic analysis shall not be confined to the response spectrum method. There must bean optional provision for Time History Analysis also. The conditions for need of using ModalResponse Spectrum Method (Dynamic Analysis) are listed, which are basically related withirregular configuration. Due to absence of definition and classification of irregularity, the usersof the code will be confused. It is desirable to include clauses that define and describe differenttypes of irregularity (horizontal, vertical, stiffness, mass, geometric and others). By suchdefinitions a clearer picture and effect of soft storey and weak storey will be available.The formula for determination of seismic coefficient has been changing in the seismic codes ofthe world. However, the base shear due to ground motion has all the time been the product ofthe seismic coefficient and the mass of the structure. The principal code factors used inderiving static lateral forces, for a long time, have basically been:Z A numeric value representing the seismic zoningI An importance factor representing the importance of the structure,especially in terms of use following a major earthquake.C A factor representing the appropriate acceleration response spectrum value.S A factor representing the effect of local soil conditions on the spectralresponse of the groundW The mass of the structure, including an assessment of live loadK A factor representing the performance of the structure depending on thebrittleness or ductility of the structure These values are combined in generalform for base shear:V = ZICKSWThis formula for base shear has been for a long time popular. However in course ofevolution the formula for the seismic coefficient has been changing. The formula for theseismic coefficient presented in the present NBE 105: 1994 considers all the above factorsexcept S-the factor representing the effect of local soil conditions on the spectral responseof the ground. This effect has been considered, like in other codes, in the response spectradrawn for different (basically three) types of soil. Thus the expression for the seismiccoefficient is given in equation 8.1. Similarly, the equation 8.2 for the expression for the
  31. 31. design response spectrum, in which the ordinate of the basic response spectrum for thenatural time period, is multiplied by ZIK.It has been a trend in the codes of the world to drop the performance factor K and replace itby reciprocal of R, response reduction factor, a factor dependant on the building type andits ductility level. The adoption of the response reduction factor leads to a realistic valuesof acceleration from which the design forces are obtained by dividing the elastic forces byit. It implies that the design force is much lower than what can be expected in the event ofa strong earthquake (Jain 2003).The replacement of the factor K by the factor 1/R may result into a logical estimation ofthe seismic coefficient, and alternate expressions derived in recent editions of codes ordocuments like NEHRP shall be given a thought for the new edition of the code.Computing dynamic response instead of using static forces is becoming increasinglycommon as higher powered computing facilities are being available in design offices.Since there is no restriction of building height and irregularity the dynamic analysisappears to be simpler in application and yields more logical and accurate results. However,special care shall be taken into consideration about conservative provision in someinternational codes. Some codes require checking of the dynamic analysis results byseismic coefficient method. Some documents like IS 1893 (Part 1) : 2002 requirecomparing the base shear with the base shear calculated using the fundamental time periodcalculated using the empirical formula recommended for static approach, and if the baseshear from dynamic analysis is less than the base shear calculated using the time periodfrom the empirical formula, all the dynamic responses shall be up-scaled multiplying bythe ratio of the two base shears. It again implies the dominance of the seismic coefficientmethod over the dynamic analysis.Seismic Hazard Level and Response SpectrumEstimate of the design ground motion is the most important and complicated part of theseismic design code development. Estimates of the design ground motion are necessarilycontroversial and uncertain. It is more important to the structural designer that this isunderstood than for him to attach some particular significance to any ground motionparameter used in his design. However there is a strong argument for conservatism in theassessment of ground motion input, and the use of high confidence level.NNBC 105: 1994 does not present any elaborate information on the seismicity of thecountry. It would be favorable to include at least maps showing epicenters of pastearthquakes, principle tectonic features, geological features including principal lithologicalgroups, and seismic zones, all of which are well documented by the Department of Minesand Geology, Nepal. Pandey et al. (2002) has presented seismic hazard map of Nepal as aresult of probabilistic seismic hazard analysis The document presents the contour ofseismic hazard at the bedrock of Nepal for a return period of 500 years, indicating 10%probability of exceedence in 50 years.The design values of ground motion parameter such as Peak Ground Acceleration (PGA)for different regions of the country are presented either in a tabular form (GB 50011-2001)or attaching relevant maps like in IBC 2006 in the codes. It is necessary to do the same inNNBC 105: 1994 also since the seismic hazard for the code was determined based on theprobabilistic seismic hazard analysis. The seismic codes adopting probabilistic approach ofhazard estimation use the hazard levels in terms of Maximum Considered/CapableEarthquake (MCE) as in NEHRP (2003) and IBC (2006), and Design Basis Earthquake(DBE) as in ATC (1978) and UBC (1997). The MCE and DBE represent 2% probability of
  32. 32. exceedence in 50 years with a return period of 2500 years and 10% probability ofexceedence in 50 years with a return period of 475 years respectively.The seismic hazards considered in earlier editions of NEHRP and UBC 97 (1997) had arecurrence interval of 475 years (Design Basis Earthquake) corresponding to a uniform 10percent probability of exceedance in 50 years, which is commonly accepted to be expectedlife of a building. The NEHRP(1997) and IBC2000(2000) had changed the Design BasisEarthquake(DBE), and since then have been using the Maximum Considered Earthquake(MCE) to represent the seismic hazards in the provisions.. The MCE represents the seismichazard that has a recurrence interval of 2500 years corresponding to a uniform 2%probability of exceedence in 50 years. The design earthquake according to the provisionsof NEHRP(2003) and IBC 2006 (2006) is two-thirds of the MCE. Comparison of theprovisions of 1994 or older editions with 1997 or later editions of the NEHRP Provisionsreveals that, a structure designed by the 1994 or older editions of NEHRP Provisions isbelieved to have a low likelihood of collapse under an earthquake that is one and one-halftimes (reciprocal of two-third) as large as the design earthquake of those documents. Thesame change has taken place from UBC 97 (1997) to IBC 2000 (2000). This major changein association with other provisions indicates the newer versions of the documents tend tobe more conservative.The seismic loading in NNBC 105: 1994 is set at a seismic hazard level having a returnperiod of 50 years, which corresponds to a probability of exceedence less than 45% in 30years, which had been estimated as the economic life of a structure in Nepal, as presentedby Beca Worley International et al.(1993), The document as well reveals that the seismichazard level was set to be at a level approximately equal to that defined in the IndianStandard, that is, IS 1893: 1984. The design earthquake level set hence is too un-conservative and strongly needs a major revision for the following reasons:i. The service life of buildings in Nepal estimated as 30 years is far from reasonable,instead it must be 50 years.ii. It is unfair to set the seismic hazard level for Nepal heavily banking upon theearthquake level stipulated in IS 1893: 1984, which has already been revised into IS1893 (Part 1): 2002 with a different value of design earthquake value. The IndianStandard has yet to adopt probabilistic format of seismic hazard analysis.iii. The provisions in the present code have been developed in reference with mainly lowrise buildings with short natural periods, where as long period structures areincreasingly becoming prevalent.iv. The seismic design lateral load calculated for short period structures as 0.08, whencompared with the basic horizontal seismic coefficient for zone V of IS 1893: 1984,found the same as 0.08. But the value according to the revised IS 1893 (Part 1): 2002will be 0.09 against 0.08.The response spectra and the zoning factors largely depends on the design earthquakelevels, and hence will be different as the seismic hazard levels change.The broad classification of soil conditions into three types is universally accepted.However, the definition and requirements of each type of them shall be more practical andrecognizable.Static Method (Seismic Coefficient Method)The seismic base shear V along any principal direction is determined by the expression:

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