Designing buildings to meet climate change challenges


Published on

Growing and potential impacts of climate change, such as flooding in coastal areas, change in weather patterns, and melting of the permafrost have created new challenges for the engineering and construction industry. These challenges involve adaptation in the design and construction of projects to address these impacts, as well as developing ways to reduce and controlling greenhouse gas (GHG) emissions to mitigate climate change.
Engineering has the lead responsibility for determining the technical feasibility and cost parameters to overcome these challenges. Engineering and construction projects are implemented with the help of a set of standard documents that lay out the work process of the projects. They include standard design detail drawings, standard design criteria, standard specifications, design guides and work process flow diagrams. Incorporating in these standard documents materials and processes which assist project engineers to identify and assess climate change related impacts can be a major step in effectively preparing to meet the challenges of climate change mitigation and adaptation.

  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Designing buildings to meet climate change challenges

  2. 2. CONTENTS : 1. Introduction 2. 3. 4. 5. 6. 7. 8. 9. Climate change & Potential Impacts Optimizing the Design Process Conceptual Design Preliminary Design Detailed Design Energy Efficient Models Conclusion References
  3. 3. INTRODUCTION :  New challenges for the construction industry • Impacts of climate change • Design to reduce GHG emissions  Engineering has the lead responsibility • For determining the technical feasibility and cost  Set of standard documents • Standard design detail drawings, standard design criteria, standard specifications • Design guides and work process flow diagrams
  4. 4. Climate change & Potential Impacts:  Climate Change  How Will Climate Change  The Contribution of Buildings to Climate Change  The Impact of Climate Change on Construction  Potential Impacts On Development
  5. 5. Climate Change: ? IPCC declared that ‘warming of the climate system is unequivocal’ – Changes in temperatures – Hot extremes, heat waves and heavy precipitation events – Tropical cyclones with larger peak wind speeds – Heavy precipitation associated with ongoing increases of tropical sea surface temperatures. – Decreases in snow cover
  6. 6. How will Climate Change: ? All parts of the world will experience significant changes in climate over this century. These changes can be summarised as: – – – – – – – Hotter, drier summers Milder, wetter winters More frequent extreme high temperatures More frequent extreme winter precipitation Significant decreases in soil moisture content in the summer Net Sea level rise and increases in sea surge height Possible higher wind speeds
  7. 7. The Contribution of Buildings: Today, buildings are responsible for more than 40 percent of global energy used, and as much as one third of global greenhouse gas emissions, both in developed and developing countries. In absolute terms: •8.6 billion metric tons CO2 eqv in 2004 •15.6 billion metric tons CO2 eqv. by 2030 (expected) Furthermore, the Buildings and Construction Sector is also responsible for significant non-CO2 GHG emissions such as halocarbons (CFCs and HCFCs) and hydro fluorocarbons (HFCs) due to their applications for cooling, refrigeration, and in the case of halocarbons, insulation materials.
  8. 8. The Impact on Construction: Climatic factors Soil Drying Temperature Relative Humidity Precipitation Impacts Increase will affect water tables and could affect foundations in clay soils Maximum and minimum changes will affect heating, cooling, air conditioning costs and thermal air movement. Frequency of cycling through freezing point will affect durability. Increase will affect condensation and associated damage or mould growth Increase and decrease will affect water tables (foundations and basements); cleaning costs will be increased in winter, with associated redecoration requirements. Gales Increase will affect need for weather tightness, risk of water ingress, effectiveness of air conditioning, energy use, risk of roof failures Radiation Increase may affect need for solar glare control Cloud Increase in winter will increase the need for electric lighting; reduction in summer may reduce the need for electric lighting for certain buildings
  9. 9. Impacts Components, sub-structures and whole buildings Air conditioning Need to upgrade airtightness Basements (sub-structure) Increased risk of heave or subsidence, water ingress, consequential damage to finishes and stored items Materials Plastics life is reduced due to increased radiation Increased salt spray zone in marine areas will reduce life duration Roofs Increased fixing costs and risk of failures due to gales, wind and Precipitation Increased cleaning costs due to wind, gales, relative humidity, precipitation. May alter construction costs and period owing to wet weather and associated loss of production. Whole building Structure/cladding/ Increased risk of cracking due to different thermal or renders/Membranes moisture movements Timber-framed Construction Increased risk of failure due to increase in relative humidity, depending on design
  10. 10. OPTIMIZING THE DESIGN PROCESS: In many respects designing to meet climate change challenges is sustainable design. A project execution approach integrating the following concepts for sustainable engineering, procurement and construction (S-EPC) is directly relevant to designing for climate change: •Site master planning and design for ecology •Process design to conserve water, energy and other natural resources •Passive design of facilities to save energy in plant and building operations, e.g. Energy Star® roofs or green (vegetated) roofs; adequate insulation of building walls, roofs, pipes, ducts and vessels, to minimize fossil-fuelled power consumption and emissions •High-efficiency HVAC and electrical systems including high-performance lighting systems integrated with daylighting and smart controls •Onsite renewable energy with energy storage for peak use, meeting the power demand that has been reduced by all of the above concepts, and resulting in reduced fossil fuel demand / emissions. •Eco-purchasing and contracting: “greening” the supply chain to minimize climate change impacts of the supply chain.
  11. 11. CONCEPTUAL DESIGN: The conceptual design phase is when sustainable design, climate change mitigation and adaptation features can be most easily incorporated into a project. During conceptual design, the integrated sustainable design team evaluates design alternatives. Project facilities, process and mechanical equipment, and building components or features should be evaluated based on their sustainability as well as feasibility and cost-effectiveness. The team should consider the maturity of the technology of the building, facility or process feature; the capital expenditure (i.e., first cost) required to procure, install, and implement the facility, building or process feature under consideration. Consider alternatives to: •Maximize energy efficiency and minimize GHG emissions: •Maximize water efficiency: •Minimize the embodied energy and carbon content of materials:
  12. 12. PRELIMINARY DESIGN: During preliminary design develop the facility energy model to confirm the design meets the established performance goals; calculate facility operations GHG emissions and materials embodied carbon content; develop a facility life-cycle cost estimate; include building information in the 3-D model. Periodically update these calculations and verify the project continues to meet the sustainable design performance goals as design progresses. The following tasks are included in this design phase: •Include sustainable engineering concepts in system design descriptions and facility design descriptions. Right-size systems and facilities using software models (not conventional rules-of thumb), avoid over-design. •Identify energy consumption by category, e.g., internal loads from the processes, building envelope loads (heat losses / gains through walls, roofs, etc.), ventilation requirements, and others.
  13. 13. Contd… • Identify energy interactions between systems and opportunities for reductions in energy requirements and cost savings through energy efficiency measures. • Develop alternative design solutions to reduce energy loads and evaluate systems as a whole. • Iterate these optimization steps and refine the system selection / design to arrive at the optimized combination of systems for energy efficiency and emissions reduction. • Update the energy model, emissions calculations, cost estimate and 3-D model to reflect the design, as it develops. Conduct a second review of progress toward meeting energy and emissions goals on the project, after the design concept is developed. This review can be concurrent with other required design reviews and is intended to confirm continued progress toward meeting the established sustainable design criteria.
  14. 14. DETAILED DESIGN & CONSTRUCTION : Continue to promote an integrated work process among all disciplines to assure continued implementation of the established energy efficiency and emissions reduction goals. Specify low embodied CO2 and energy content materials. Include embodied energy and CO2 evaluation criteria in technical bid evaluations. Specify materials available locally. Consider construction waste management options, construction vehicle options, etc. Finalize the: •Energy model •3-D model with building information •GHG emissions calculations •Life-cycle cost estimate Conduct a third and final review of the design relative to the energy efficiency and emissions reduction goals.
  15. 15. ENERGY EFFICIENCY MODELS: THERE ARE DIFFERENT LOGICS in pursuing the energy efficiency of buildings, ranging from lower to higher technological approaches. These are models that can be applied to improve energy efficiency in buildings; • Low- and zero-energy buildings • Passive housing de-sign • Energy-plus buildings • EcoCities • Refurbishment aspects • Commissioning processes.
  16. 16. Low Energy Buildings: The Definition of low-energy building can be divided into two specific approaches: The concept of 50% & The concept of 0% A building constructed using the 50% concept consumes only one half of the heating energy of a standard building. The low energy consumption is based on an increased level of thermal insulation, high performance windows, airtight structural details and a ventilation heat recovery system. In USA-Arizona, USA-Grand Canyon (California), Belgium, Canada, Denmark, Finland, Germany, Italy, Japan, the Netherlands, Norway, Sweden and Switzerland zero energy buildings were built.
  17. 17. Zero Energy Buildings: Zero-energy buildings(an ultra-low-energy buildings) are buildings that produce as much energy as they consume over a full year. Energy can be stored on site, in batteries or thermal storage. The grid can be used as seasonal storage via net metering, as some buildings produce more in the summer and use more in the winter, but when the annual accounting is complete, the total net energy use must be zero. Buildings that produce a surplus of energy are known as energy-plus buildings. The Worldwide Fund for Nature (WWF) zero-energy housing project in the Netherlands & The Malaysia Energy Centre (Pusat Tenaga Malaysia) headquarters are zero-energy office (ZEO) buildings.
  18. 18. Passive Houses:  A passive house is a building in which a comfortable interior climate can be maintained with-out active heating and cooling systems. The house heats and cools itself, and is therefore ‘passive’. Characteristics of passive houses Compact form and good insulation: U-Factor <=0.15W/(m2K) Orientation and shade considerations: Passive use of solar energy Energy-efficient window glazing and U-Factor <=0.80W/(m2K) {glazing and frames, combined} frames: solar heat-gain coefficients around 50% Building envelope air-tightness: Air Leakage <=0.61/hour Passive pre heating of fresh air: Fresh air supply through underground ducts that exchange heat with the soil. This preheats fresh air to a temperature above 5oC, even on cold winter days Highly efficient heat recovery from Heat recovery rate over 80% exhaust air: Hot water supply using regenerative Solar collectors or Heat pumps energy sources: Energy-saving household appliances: Low energy refrigerators, stoves, freezers, lamps, washers, dryers, etc. are indispensable in a passive house
  19. 19. Eco Cities: In order to render the building energy efficient, the whole energy chain has to be considered, including the local environmental conditions, community issues, transportation systems and working and living structures. Eco Cities are settlement patterns for sustainable cities, which were developed in a project supported by the European Union. The energy chain for buildings in Eco Cities includes the following items: > Low-energy houses; > Low-temperature heating systems; > Low-temperature heat distribution system; > Use of renewable energy sources whenever possible; > Heat production as near as possible; > Electricity production;
  20. 20. CONCLUSIO N to  Designing : meet the challenges of climate change does not require a completely new design process. Incorporating sustainable design considerations into the conventional design process can result in more energy efficient and lower GHG emitting designs if sustainable design performance goals are set early in the project development and regularly monitored to assure the evolving design continues to support achieving the goals.  And when considered in the context of the overall life- cycle cost of a project, sustainable design will reduce life-cycle costs and produce significant benefits for climate change.
  21. 21. REFERENCES :  Dr. R. B. Draper, Dr. P Attanayake (2010),” DESIGNING TO       MEET CLIMATE CHANGE CHALLENGES”, International Conference on Sustainable Built Environment (ICSBE-2010). Sylvie Lemmet, (2010), “SUSTAINABLE BUILDINGS AND CLIMATE INITIATIVE”, Sustainable united Nations. “BUILDINGS AND CLIMATE CHANGE” - Status, Challenges and Opportunities by United Nations Environment Programme, 2007. Gardiner, Theobald (2006), “ADOPTING TO CLIMATE CHANGE IMPACTS: A good practice guide for sustainable communities”. Michael J. Holmes, Jacob N. Hacker (2007), “CLIMATE CHANGE, THERMAL COMFORT AND ENERGY: Meeting the design challenges of the 21st century” N.J. Cullen BSc(Hons), “CLIMATE CHANGE –DESIGNING BUILDINGS WITH A FUTURE”, National Conference 2001 MarkSnow, Deo Prasad (2011), “CLIMATE CHANGE ADAPTION FOR BUILDING DESIGNERS”, Australian Institute of Architects.
  22. 22. ? R.RAGHAVENDRA