This document provides information on various low cost building components that can be used for construction. It discusses precast solid cement concrete blocks, precast concrete stone masonry blocks, hollow and solid lightweight concrete masonry units, precast reinforced concrete door and window frames, ferrocement roofing channels, and other components. These alternative materials provide benefits like reduced cost, improved strength and durability, thermal efficiency, and environmental sustainability compared to traditional building materials.

1. LOW COST BUILDING COMPONENTS
GUIDED BY:
AR. ASHU JAIN
PRESENTED BY:
SAKSHI JAIN
IV YEAR
housing

2. CONTENT:
 INTRODUCTION
 LOW COST BUILDING COMPONENTS
 PRECAST SOLID CEMENT CONCRETE BLOCK
 PRECAST CONCRETE STONE MASONRY BLOCK
 HOLLOW AND SOLID LIGHTWEIGHT CONCRETE MASONRY UNITS
 PRECAST REINFORCED CONCRETE DOOR AND WINDOW FRAMES
 FERROCEMENT ROOFING CHANNEL
 FERROCEMENT DOOR SHUTTER
 PRECAST FERROCEMENT WATER TANK
 PRECAST CONCRETE MANHOLE COVER & FRAMES
 BAMBOO MAT CORRUGATED ROOFING SHEET.

3. Introduction:
BUILDING COMPONENTS OR PARTS ARE ESSENTIAL MATERIALS FOR BUILDING
CONSTRUCTION. ALL BUILDINGS BUILT WITH THE SAME COMPONENTS SUCH AS
FOUNDATIONS, WALLS, FLOORS, ROOMS, AND ROOFS.
BUILDINGS NEED TO DECORATE OR RENOVATE WITH PAINTS, PLASTERS, SUPPLIED
ELECTRICITY, AND DOORS AND WINDOWS FITTINGS, FENCING, AND EXTERNAL OTHER
WORKS TO FINISH ACCURATELY. ALL THESE WORKS CALLED BUILDING SERVICE.
 A BUILDING HAS THREE BASIC
REQUIREMENTS AND COMPONENTS. THEY ARE –
FOUNDATION
PLINTH
SUPERSTRUCTURE
i. FLOOR AND ROOF
ii. PARAPET
iii. LINTEL
iv. SUNSHADE
v. WALLS & COLUMNS
vi. DOOR & WINDOWS

4.  REDUCED EMBODIED ENERGY
THROUGH FUEL CONSUMPTION AND
LESS ENERGY INTENSIVE MATERIAL
 REDUCED ENVIRONMENTAL
DAMAGE THROUGH OPTIMAL
RESOURCE USE AND WASTE
UTILIZATION.
 BETTER THERMAL EFFICIENCY AND
COMFORT.
 RESISTANT TO NATURAL DISASTERS.
 ALIGNED TO LOCAL PRODUCTION IN
TERMS OF MATERIAL AND SKILL
AVAILABILITY.
 COST EFFICIENCY.
Low Cost BUILDING COMPONENT :
 LOW COST IS A NEW CONCEPT WHICH DEALS
WITH EFFECTIVE BUDGETING AND
FOLLOWING OF TECHNIQUES WHICH HELP
IN REDUCING THE COST CONSTRUCTION
THROUGH THE USE OF LOCALLY AVAILABLE
MATERIALS ALONG WITH IMPROVED SKILLS
AND TECHNOLOGY.
BENEFITS OF ALTERNATE BUILDING
TECHNOLOGIES :

5. AREAS FROM WHERE COST CAN BE REDUCED ARE:-
 REDUCE PLINTH AREA BY USING THINNER WALL
CONCEPT. EX.15 CMS THICK SOLID CONCRETE BLOCK
WALL.
 USE LOCALLY AVAILABLE MATERIAL IN AN
INNOVATIVE FORM LIKE SOIL CEMENT BLOCKS IN
PLACE OF BURNT BRICK.
USE ENERGY EFFICIENCY MATERIALS WHICH
CONSUMES LESS ENERGY LIKE CONCRETE BLOCK.
USE ENVIRONMENTALLY FRIENDLY MATERIALS WHICH
ARE SUBSTITUTE FOR CONVENTIONAL BUILDING
COMPONENTS LIKE USE R.C.C. DOOR AND WINDOW
FRAMES IN PLACE OF WOODEN FRAMES.
BY PLANNING EACH AND EVERY COMPONENT OF A
HOUSE THE WASTAGE OF MATERIALS DUE TO
DEMOLITION OF THE UNPLANNED COMPONENT OF THE
HOUSE CAN BE AVOIDED

6. A CONCRETE BLOCK ALSO CALLED A CONCRETE
MASONRY UNIT (CMU) IS PRIMARILY USED IN BUILDING
CONSTRUCTION OF WALLS. A CONCRETE BLOCK IS ONE OF
SEVERAL PRECAST CONCRETE PRODUCTS USED IN
CONSTRUCTION.
LIGHTWEIGHT CONCRETE BLOCKS ARE MADE BY
REPLACING THE SAND AND GRAVEL WITH EXPANDED CLAY,
SHALE, OR SLATE.
PRECAST CONCRETE BLOCK
PRECAST SOLID CEMENT CONCRETE BLOCK
THE TERM PRECAST REFERS TO THE FACT THAT THE
CEMENT CONCRETE BLOCKS ARE FORMED AND HARDENED
BEFORE THEY ARE BROUGHT TO THE JOB SITE. SIZES OF THE
PRECAST CEMENT CONCRETE BLOCK ARE:
LENGTH : 400, 500 OR 600 MM
HEIGHT : 200 OR 100MM
WIDTH : 50, 75, 100, 200, 250 OR 300MM

7. ADVANTAGES OF PRECAST SOLID CEMENT CONCRETE
BLOCK:
HIGH COMPRESSIVE STRENGTH.
A GOOD FIRE AND ABRASION RESISTANCE.
VERY GOOD STABILITY.
RAPID CONSTRUCTION.
HOLLOW UNITS HAVE LOW SELF-WEIGHT.
REINFORCEMENT CAN BE PASSED THROUGH HOLLOW
UNITS AND FILLED WITH CONCRETE TO INCREASE
EARTHQUAKE RESISTANCE.
THE EMBODIED ENERGY OF CONCRETE BLOCK IS 1.5
MJ/KG.

8. PRECAST CONCRETE STONE MASONRY BLOCK:
PRECAST CONCRETE STONE MASONRY BLOCKS ARE USED FOR BOTH LOAD-BEARING
AND NON-LOAD BEARING WALLS, FOR PARTITIONS AND PANEL WALLS, AS BACKING FOR
OTHER TYPES OF FACING MATERIAL, FOR PRERS, PILASTERS AND COLUMNS, FOR
RETAINING WALLS AND GARDEN WALLS.
PRECAST CONCRETE STONE MASONRY BLOCKS,
ALREADY EXTENSIVELY USED IN BUILDING
CONSTRUCTION IN AREAS WHERE STONE IS LOCALLY
AVAILABLE, ARE LIKELY TO MAKE CONSIDERABLE
HEADWAY THROUGHOUT THE COUNTRY BECAUSE OF
THE MANY ADVANTAGES, SUCH AS STRENGTH,
STRUCTURAL STABILITY, THIN WALLS, BETTER
AESTHETIC LOOK, LIGHT FOUNDATION LOAD, ETC.

9. Precast concrete stone masonry block construction is economical because of following
aspects:
 THE UNITS ARE TRUE IN SIZE AND SHAPE. THIS ENSURES
RAPID CONSTRUCTION SO THAT MORE WALL AREA IS
CONSTRUCTED PER MAN-HOUR THAN RANDOM RUBBLE OR
BRICK MASONRY CONSTRUCTION.
 FEWER JOINTS RESULT IN CONSIDERABLE SAVING IN
MORTAR AS COMPARED TO NORMAL MASONRY
CONSTRUCTION.
 THE TRUE PLANE SURFACES OBTAINED OBVIATE THE
NECESSITY OF PLASTER FOR UNIMPORTANT BUILDINGS
SITUATED IN LOW RAIN FALL AREA,
BECAUSE OF UNIFORM SHAPE AND SIZE OF THE UNITS, CONSIDERABLY THINNER
WALLS ARE POSSIBLE AS COMPARED TO RANDOM RUBBLE MASONRY WALLS, THUS
INCREASING THE EFFECTIVE FLOOR SPACE AND REDUCING THE LOAD ON
FOUNDATION.

10. ADVANTAGES:
THEY PROVIDE SUPERIOR RESISTANCE TO FIRES,
NATURAL DESASTER, INSECTS AND MOLD.
ITS RESISTANCE TO RAIN, WIND DAMAGE,
EARTHQUAKES, TERMITES AND DECAY PROVIDES
LOWER MAINTENANCE AND INSURANCE COSTS.
PRECAST CONCRETE CAN TAKE NEARLY ANY
SHAPE OR SIZE, BE MANUFACTURED IN VIRTUALLY
ANY COLOR AND COMES IN A WIDE VARIETY OF
FINISHES.
PRECAST CONCRETE IS COMPLETELY RECYCLABLE, MAKING IT AN
ENVIRONMENTALLY FRIENDLY CHOICE.

11. Hollow and solid light weight masonary unit
 CONCRETE HOLLOW BLOCKS ARE INNOVATIVE BUILDING
PRODUCTS THAT ARE USED AS SUBSTITUTES FOR
TRADITIONAL BRICKS IN BUILDING CONSTRUCTION. THEY
HAVE AN INNER VOID AREA WHICH IS GREATER THAN 25%
OF THEIR GROSS AREA AND ARE AVAILABLE IN VARIOUS
SIZES AND SHAPES. CONCRETE HOLLOW BLOCKS ARE
MACHINE-MADE AND UNAFFECTED BY WEATHER
CONDITIONS UNLIKE THE RED BRICKS.CONCRETE HOLLOW
BLOCKS ARE MAINLY USED FOR THEIR DURABILITY, LOW
COST, SPEED OF CONSTRUCTION, AND ECO-FRIENDLINESS
BESIDES OTHERS.
 EMBODIED ENERGY OF HOLLOW CONCRETE BLOCK IS 0.67
AND BRICK IS 3.
 CARBON FOOTPRINT OF HOLLW CONCRETE BLOCK IS 0.073
AND BRICK IS 0.24.

12. ADVANTAGES
 HIGHLY DURABLE: THE GOOD CONCRETE COMPACTED BY HIGH
PRESSURE AND VIBRATION GIVES SUBSTANTIAL STRENGTH TO THE
BLOCK.
 LOW MAINTENANCE, COLOR AND BRILLIANCE OF MASONRY
WITHSTANDS OUTDOOR ELEMENTS.
 LOAD BEARING, STRENGTH CAN BE SPECIFIED AS PER THE
REQUIREMENT.
 FIRE RESISTANT
 PROVIDE THERMAL AND SOUND INSULATION: THE AIR IN HOLLOW
OF THE BLOCK, DOES NOT ALLOW OUTSIDE HEAT OR COLD IN THE
HOUSE. SO IT KEEPS HOUSE COOL IN SUMMER AND WARM IN
WINTER.
 ECONOMICAL
 ENVIRONMENT FRIENDLY, FLY ASH USED AS ONE OF THE RAW
MATERIALS.

13. DISADVANTAGES
 DURING EXTREME WEATHER, IT MAY CAUSE DEGRADATION OF THE
SURFACE DUE TO FROST DAMAGE.
 IT ADDS A LOT OF WEIGHT TO THE FOUNDATION. THEREFORE IT
INCREASES THE STRESS OF THE FOUNDATION WHICH STRONGER
FOUNDATION NEEDED TO SUPPORT THIS BRICKS.
 WHEN THE BRICK SHOW SOME DAMAGE, IT IS UNABLE TO REPAIR THAT
PART ONLY BUT TO REMOVE THE ENTIRE WALL SECTION WHICH VERY
COSTLY. PLUS, MATERIAL USED ARE LARGELY RELATED.
 POORLY MADE BRICKS SUCH AS CLINKERS AND OLDER RECYCLED
BRICKS MIGHT BE PITTED, IRREGULARLY SHAPED, WORN OR PRONE TO
CHIPPING.
 IN HUMID CLIMATES, POROUS BRICK INVITES MOLD. IT SUFFERS
DAMAGE AS WATER AND ICE EXPAND AND CONTRACT IN ITS PORES.
 BRICK IS NOT COST-EFFECTIVE FOR MANY HOME BUILDERS. IT CAN BE
DAMAGED BY VINES.

14. Precast reinforced concrete door and window frames
▪ WITH FAST DEPLETION OF THE FOREST RESOURCES TIMBER HAS NOW BECOME A
SCARCE MATERIAL. THIS HAS NECESSITATED SEARCH FOR SUBSTITUTE MATERIALS
FOR MAKING FRAMES FOR DOORS AND WINDOWS.
▪ PRECAST RC FRAMES ARE ALTERNATE TO TRADITIONAL TIMBER FRAMES FOR DOORS
AND WINDOWS AND ECONOMICAL COMPARED TO FRAMES MADE OUT OF
TRADITIONAL TIMBERS LIKE TEAK AND DEODAR.
▪ THEY ARE MORE SUITABLE THAN TIMBER FRAMES IN WET AREAS LIKE LAVATORIES,
BATHROOMS AND KITCHENS AND ARE RESISTANT TO TERMITE ATTACH AND GROWTH
OF FUNGUS.
▪ THE RCC FRAMES ARE BETTER RESISTANT TO FIRE AS COMPARED TO WOODEN
FRAMES. THEY COST ABOUT HALF THE PRICE OF COUNTRY TEAKWOOD AND ARE
BECOMING INCREASINGLY POPULAR, ESPECIALLY FOR LOW-COST HOUSES. THE
DETAILS OF DOORS AND WINDOWS WITH R.C.C.

16. DIMENSIONS AND MATERIAL
▪ PRECAST REINFORCED CONCRETE DOOR AND WINDOW FRAMES SHALL BE 60 X 100
MM OR 70 X 75 MM IN CROSS-SECTION FOR SINGLE SHUTTER DOOR AND 60 X 120 MM
FOR DOUBLE SHUTTER DOOR.
▪ THE MATERIALS USED FOR THE MANUFACTURE OF PRECAST REINFORCED CONCRETE
DOOR AND WINDOW FRAMES:
▪ AGGREGATES-THE AGGREGATES USED SHALL CONSIST OF WELL-GRADED MIXTURE OF
CLEAN COARSE AND FINE AGGREGATES THE NOMINAL MAXIMUM SIZE OF COARSE
AGGREGATES SHALL NOT EXCEED 10 MM.
▪ CONCRETE-THE MIX PROPORTION OF THE CONCRETE SHALL BE DETERMINED BY THE
MANUFACTURER AND SHALL BE SUCH AS TO PRODUCE A DENSE CONCRETE NOT
WEAKER THAN GRADE M20.
▪ REINFORCEMENT- STEEL REINFORCEMENT SHALL BE MINIMUM OF 3 BARS OF 6 RNM DIA
OR EQUIVALENT OF ABOUT 1'5 PERCENT OF THE SECTIONAL AREA OF THE CONCRETE
MEMBER.

17. BENEFITS OF PRECAST RCC DOOR AND WINDOW FRAMES
REINFORCED CEMENT CONCRETE, AS AN
ALTERNATIVE BASE MATERIAL FOR PRODUCING
DOOR AND WINDOW FRAMES, HAS BEEN AROUND
FOR SOME TIME NOW. ITS TECHNICAL AND
ECONOMIC BENEFITS HAVE BEEN EXTENSIVELY
DOCUMENTED AND PROMOTED BY THE
GOVERNMENT, THROUGH VARIOUS GOVERNMENT
AND SEMI GOVERNMENT AGENCIES.
THE GOVERNMENT HAS BANNED USE OF WOOD IN
ALL GOVERNMENT CONTROLLED CONSTRUCTION
ACTIVITY, REPLACING IT WITH STEEL AND
ALUMINUM. THE PRIVATE SECTOR STILL CONTINUES
TO USE WOOD EXTENSIVELY.
RCC WAS INTRODUCED AS AN ALTERNATIVE
MATERIAL TO PRODUCE DOOR AND WINDOW
FRAMES WITH THE BENEFITS– LOW COST, STURDY
PRODUCT, TERMITE AND MOISTURE RESISTANT,
STRUCTURALLY SOUND AND EASILY AVAILABLE
MATERIAL AND MANPOWER.
OVERALL DIMENSIONS OF PRECAST
REINFORCED CONCRETE DOOR FRAME

18. FERROCEMENT:
 FERROCEMENT IS A HIGHLY VERSATILE FORM OF R.C.C
POSSESSING UNIQUE PROPERTIES OF STRENGTH AND
DURABILITY. IT IS MADE UP OF RICH CEMENT MORTAR
AND WIRE MESH REINFORCEMENT.
 ADVANTAGE OF FERROCEMENT OVER CONVENTIONAL
BUILDING MATERIALS ARE:
• COST - EFFECTIVENESS COMPARED TO R.C.C
• LOWER INTENSITY OF MATERIAL USE
• SPEEDY PROCESS OF CONSTRUCTION
• FLEXIBILITY WITH REGARDS TO CUTTING, DRILLING &
JOINING
• HIGH ACCEPTABILITY IN TERMS OF SHAPE AND FORM
• MORE ENERGY EFFICIENT THAN THEIR EQUIVALENTS
MADE IN REINFORCED CEMENT CONCRETE
PRECAST ROOFING ELEMENTS
IN BANGALORE
INTERNATIONAL AIRPORT

19. FERROCEMENT ROOFING CHANNEL:
 FERROCEMENT ROOFING CHANNELS ARE
ESSENTIALLY PREFABRICATED, CYLINDRICAL
SHELL UNITS HAVING DEFINED SHAPE AND SIZE.
 THE LENGTH OF THESE CHANNEL UNITS EQUALS TO
THE LENGTH OF THE ROOM TO BE ROOFED.
 THE THICKNESS OF THESE ELEMENTS IS JUST 25
MM. THIS IS THE REASON WHY FERROCEMENT
ROOFING CHANNELS ENABLE COST SAVINGS UPTO
40% AND SAVES ENERGY UPTO 25% IN COMPARISON
WITH R.C.C ROOF.
 A CHANNEL UNIT USES APPROXIMATELY 3 KG OF
STEEL IN THE FORM OF MILD STEEL BARS AND WIRE
MESH REINFORCEMENT PUT TOGETHER PER SQM OF
ROOFING AREA WHEREAS R.C.C USES 7-10 KG OF
STEEL PER SQM. OF ROOF AREA.
MOULD FOR PRECAST FERROCEMENT
ROOFING CHANNEL
FERROCEMENT ROOFING

20.  FERROCEMENT CHANNELS ARE PREFABRICATED AND
CURED FOR A PERIOD OF 2-3 WEEKS, AFTER WHICH THEY
ARE READY FOR ROOF CONSTRUCTION.
 USE OF THESE CHANNELS SAVES 3 WEEKS OF
CONSTRUCTION TIME AS NO SHUTTERING IS INVOLVED.
 THE COMPARISON OF STRENGTH, PERFORMANCE AND
OTHER ASPECTS OF FERROCEMENT CHANNELS WITH
TRADITIONAL AND CONVENTIONAL FLAT ROOFING
OPTIONS ARE TABULATED AS FOLLOWS:
PARAMETERS
REINFORCED
CEMENT CONCRETE
ROOFING
STONES
REINFORCED
BRICK CEMENT
FERROCEMENT
ROOFING
STRENGTH TO WEIGHT
RATIO
LOW VERY LOW MEDIUM HIGH
PERFORMANCE HIGH MEDIUM MEDIUM HIGH
DURABILITY HIGH MEDIUM LOW HIGH
EQUIPMENTS FOR ROOF SHUTTERING REQUIRED NO SHUTTERING
SHUTTERING
REQUIRED
NO SHUTTERING
SKILLS REQUIRED SKILLED HIGHLY SKILLED HIGHLY SKILLED SEMI SKILLED
COST RANGE (RS.) FOR A
SPAN 3.6-6.0 M
450-600 400-500 400-550 375-450
EMBODIED ENERGY OF FCRC
IS 620 MJ/SQ.M AS COMPARED TO
750 MJ/SQ.M FOR A 4’’ THICK RCC
ROOF

21. ADVANTAGES:
 FERROCEMENT CHANNEL ROOF PROVIDES LIGHT
WEIGHT ROOFING – 60% REDUCTION IN DEAD WEIGHT
AS COMPARE TO RCC
 20% SAVING IN COST POSSIBLE BECAUSE OF
REDUCTION IN STEEL QUANTITY AND ELIMINATION OF
COARSE AGGREGATES AND SHUTTERING
 CREATES EMPLOYMENT AS THE ROOF COMPONENTS
CAN BE LOCALLY PRODUCED AND DELIVERED
THROUGH MICRO LEVEL ENTERPRISE
 MUCH BETTER QUALITY CONTROL CAN BE
MAINTAINED DURING PRE-FABRICATION
 VERSATILE TECHNOLOGY - W.R.T PROFILES OF ROOFING
CHANNELS (SUBJECT TO STRUCTURAL DESIGN)
 DOUBLE LAYERED STACKING OF CHANNELS IS
POSSIBLE, IF STACK AREA IN SITE IS LESS.

22. FERROCEMENT DOOR SHUTTERS
 THE MATERIALS REQUIRED ARE COMMONLY AVAILABLE
 MANUFACTURING TECHNIQUES CAN BE TAUGHT TO SEMI -
SKILLED LABOUR.
 ONLY MANUAL LABOR IS INVOLVED IN MANUFACTURING THE
BASIC FERROCEMENT DOOR PANELS.
 FERROCEMENT DOORS ARE STRONG, DURABLE, FIREPROOF,
WATERPROOF AND TERMITE RESISTANT.
Introduction:
A FERROCEMENT DOOR IS EASY TO MANUFACTURE, THE
PREFABRICATED DOOR IS STRONG AND DURABLE, IS RESISTANT
AGAINST WATER AND REQUIRES LITTLE MAINTENANCE
AFTERWARDS. AUROVILLE BUILDING CENTRE HAS BEEN USING
THE PREFABRICATED TECHNIQUE OF CASTING DOORS SINCE 1986.
ADVANTAGES:

23.  FERROCEMENT DOORS CAN BE MADE ON ANY FLAT SURFACE WITH
ORDINARY MASON TOOLS AND ARE EASY TO TRANSPORT AND
INSTALL.
 A DAMAGED FERROCEMENT DOOR CAN BE REPAIRE.
 THE WEIGHT OF A FERROCEMENT DOOR OF 12 MM THICKNESS IS
APPROXIMATELY 30 KG/M2 (AS COMPARED TO WOODEN DOORS
WEIGH APPROXIMATELY 18 KG/M2)
 THE HINGES AND LOCKS HAVE TO BE INSTALLED AFTERWARDS
WHICH NECESSITATES THE USE OF A POWERED HAND DRILL AND
MASONRY DRILL BITES OF VARIOUS DIAMETERS.
 THE LOCK STILL HAS TO BE SURFACE MOUNTED DUE TO THE
THICKNESS OF THE DOOR PANEL, THIS LIMITS THE CHOICE OF
LOCK.
 AFTER THE CASTING AND INITIAL CURING ARE COMPLETED CARE
AND EXPERIENCE IS REQUIRED TO AVOID BREAKING THE THIN
PANEL WHILE LIFTING IT OFF FROM THE CASTING SURFACE.
 CARE HAS TO BE TAKEN THAT NO DAMAGE OCCURS DURING
TRANSPORTATION.
DISADVANTAGES:

24. APPLICATIONS
 THEY CAN REPLACE STEEL DOORS IN INDUSTRIAL SETTINGS
AND LOW-COST WOODEN DOORS FOR HOUSING PROJECTS
BECAUSE OF THEIR STRENGTH, DURABILITY AND ECONOMY.
 THEY CAN REPLACE ASBESTOS PANEL DOORS IN BATHROOMS,
BECAUSE THEY ARE WATERPROOF AND DO NOT POSE HEALTH
OR ENVIRONMENTAL HAZARDS.
 THEY CAN BE USED AS BALCONY OR BACK DOORS BECAUSE
OF THEIR DURABILITY, WATERPROOF AND NON-WARPING
QUALITIES.
 THEY CAN BE USED AS DOUBLE DOORS FOR LARGER
OPENINGS.
 THEY CAN BE MANUFACTURED IN DIFFERENT SHAPES AND
STYLES FOR DIFFERENT APPLICATIONS AND CAN BE
DECORATED WITH PLASTER OF PARIS ORNAMENTS FOR A
SUPERB FINISH.

25. PRECAST FERROCEMENT WATER TANK

26. PRECAST CONCRETE MANHOLE COVER & FRAMES
 A MANHOLE COVER IS A REMOVABLE PLATE FORMING
THE LID OVER THE OPENING OF A MANHOLE, TO
PREVENT ANYONE OR ANYTHING FROM FALLING IN,
AND TO KEEP OUT UNAUTHORIZED PERSONS AND
MATERIAL.
 THE BEARING SURFACES OF MANHOLE FRAMES AND
COVERS ARE MACHINED TO ASSURE FLATNESS AND
PREVENT THEM FROM BECOMING DISLODGED BY
TRAFFIC.
 SHAPES OF MANHOLE COVERS AND FRAMES:
 ROUND STRUCTURES
 RECTANGLE / SQUARE STRUCTURES
 MANUFACTURING METHODS
 WET- CAST
 DRY- CAST(MACHINE MADE)

27. CORRUGATED BAMBOO ROOFING SHEETS
CORRUGATED BAMBOO ROOFING SHEETS (CBRS) ARE AN
EXCELLENT ALTERNATIVE TO CORRUGATED METAL,
PLASTIC OR ASBESTOS ROOFING SHEETS. THEY ARE
PRODUCED FROM A NATURAL AND SUSTAINABLE
RESOURCE AND CAN BE USED TO COVER HOMES, OTHER
TEMPORARY OR PERMANENT STRUCTURES.
Manufacturing:
PROCESS OF PRODUCING CBRS INVOLVES 6 STEPS:
• BAMBOOS ARE SPLIT INTO THIN SLIVERS.
• SLIVERS ARE WOVEN INTO MATS.
• MATS ARE SOAKED IN ADHESIVE RESIN.
• MATS ARE ALLOWED TO DRAIN AND DRY.
• MATS ARE GLUED TOGETHER UNDER HIGH TEMPERATURE AND PRESSURE.
• SHEETS ARE TRIMMED TO SHAPE.
INTRODUCTION

28.  BAMBOO ROOFING SHEETS ARE ENVIRONMENTALLY FRIENDLY
AND A SAFE ALTERNATIVE TO PLASTIC, ZINC OR CORRUGATED
ASBESTOS ROOFING PANELS.
 THEY HAVE THE SAME STANDARD MEASUREMENTS AS
CONVENTIONAL CORRUGATED ROOFING SHEETS.
 BAMBOO ROOFS ARE QUIETER IN THE RAIN AND COOLER IN
THE SUN THAN CONVENTIONAL METAL OR PLASTIC SHEETS.
 BAMBOO SHEETS ARE DURABLE AND STRONG WITH
EXCELLENT INTERNAL BOND STRENGTHS AND A HIGH
RESISTANCE TO WEATHERING, FIRE OR INSECT ATTACKS.
 THEY HAVE AN ATTRACTIVE AND NATURAL APPEARANCE AND
ARE EASY TO WORK WITH
ADVANTAGES