Construction Industry and its Impact to Built Environment

2. Construction Industry and its Impact to Built Environment

3. Construction Industry account for one-sixth of the world's fresh water withdrawals, one-quarter of its wood harvest.  The cement sector alone accounts for 5 % of global man made CO2 emissions

4. Construction & Demolition (C&D) generate between 10% and 40% of the solid waste stream in most countries (Kibert et al, 2000). C&D wastes can generally be used for low-priority works like footpaths, drains, pavements etc. Most bonding & drying agents in carpets, veneers, particle board, plywood and paint emit volatile organic compounds (VOC’s) which contribute to greenhouse gases and global warming. Pollution and Waste

5. Environmental impacts • Resource depletion • Physical disruption • Chemical pollution • Other effects; • Social disruption, undesirable visual impact. • Social impacts • Loss of open space & • biodiversity • Social Isolation • Increased car • dependency • Decreased air quality • Unhealthy indoor • environment Economic impacts • To Builders: • Increased compliance • costs & waste disposal • costs • To Owners: • Increased utility & • maintenance costs • To Occupiers: • Loss of well being & • productivity • To Society: • Decreased • environmental quality

6. According to the World Watch Institute about 40% of the world's total energy usage is dedicated to the construction and operation of buildings. • The building industry consumes 3 billion tons of raw materials annually, 40% of the total material flow in the global economy. • Only about 0.003 % of earth's water is readily available as fresh water for human use (Miller, 1992). Building materials manufacturing, construction and operations consumes 16% of available fresh water annually • In 1990 the building industry consumed 31% of Global energy and emitted 1900 Megaton's of Carbon.

7. Towards an innovative & eco-friendly Construction Industry

8. GREEN Building • ‘Continued ability of a society, an ecosystem, or any such interactive system to function without exhausting key resources and without adversely affecting the Environment’ • Principles: • Maximizing the use of renewable and natural resources; • Minimizing the use of energy and water;

9. Green Buildings Materials • Green building materials offer specific benefits to the building owner and building occupants: • Reduced maintenance/replacement costs over the life of the building; • Energy conservation and reduce harmful emissions; • Improved occupant health and productivity; • Lower costs associated with changing space configurations; • Do not exhaust the existing supplies of finite materials;

10. Choosing Building Materials Underlining Principle: Assuming that all stages in the life of a material right from extraction, manufacture, transportation to the installation, operation, maintenance and the recycling and waste management cause some degree of Environmental impact which needs to be evaluated.- This is called Life Cycle Analysis (LCA) for any material/product.

11. Characteristics of Sustainable Managed Alternatives • 1. CEMENT CONCRETE • Energy Intensive industry • Depletion of natural resources • Green house gas emissions

12. Recommended Alternatives: • Blast furnace Slag Concrete • Using Ground Granulated Blast Furnace slag with Cement (from steel plants) in mixes

13. Recommended Alternatives: • Using Recycled Aggregates • Crushed Concrete, Bricks and other masonry waste

14. 3. Mortars and Plasters: • Basic Mortar used: 1 : 6 (Cement : Sand) • Cement : Lime : Sand (1 : 1 : 6)

15. Lime : rha : Sand (1 : 1 : 1) • rha: Rice husk ash - hard protecting coverings of grains of rice (burnt)

16. Our predecessors knew it better…….We were much less resource dependent in the past Looking back to think ahead……………..

17. RAMMED EARTH AND MUD BLOCKS CONSTRUCTION IN BHUTAN

18. Earthen Construction TechnologyA brief History Tabo Monastery , HP – India , 996 AD Auroville-Earth Institute Shey Monastery, Ladakh 17th Century Ramasseum, Egypt Around 1300BC Our Very Own Aman, Gangtey

19. Innovative Building Technologies: • Hollow Interlocking-Compressed Stabilized Earth Block • (HI-CSEB)

20. Innovative Building Technologies: • Machine that produces HI-CSEB, developed by Auroville Earth Institute, Tamil Nadu, India Aurum Press 3000

21. HI-CSEB • Economical/affordable, environmentally friendly, easily available, stronger, energy saving and simple to • manufacture • Better Thermal Insulation • Warm in winter and cool in summer

22. Technical /Engineering Aspects • Block Production • Material selection • Soil Identification – Top soil and soil with organic matter should not be used. • Grain size distribution - more of sandy is preferred.

23. Some basic test for identifying the suitability of soil

24. Proportions • Cement : Soil (1 : 6) • Water content = 25 liters for one bag of cement • Varying the ratio esp. the cement has the proportionate cost involved • The ratio can go up to 1 cement to 10 soil

25. Same basic data on CSEB

26. Comparison with other building blocks For a 250mm thick 1msq wall in a load bearing building @ Thimphu

27. Block production machines • Two Machines in the market • HI – CSEB Block machine – Habitech centre, Thailand 2) AURUM PRESS 3000 – Auroville,India

28. Pilot House Construction – SQCA using HI – CSEB 245 • Two storied load bearing structures - serve as model for the earthquake resistant design features • Sample Blocks test results

29. SQCA – Pilot Project

30. Hollow Interlocking –Compressed Stabilized Earth Block (HI-CSEB)

31. Pilot house using HI-CSEB

32. Some other buildings using HI-CSEB

33. Advantages • Use of cheap & locally available materials • Job opportunity for local people • Biodegradable materials • Energy efficiency and eco friendliness 5 – 15 times less energy consumed than fired brick and around 3 – 8 times less emission • Transferable technology • Import Reduction

34. Advantages 7. Cost effectiveness 8. Minimum mortar required 9. Keys that interlock with each other provides better integrity 10. Hollow provisions for laying vertical and horizontal reinforcements to improve the lateral load resisting capacity 11. Ease and Fastness in construction 12. Fire resistant

35. Limitations • Only for low rise structures: maximum 2 storey • Strength very much dependant on the properties of soil • Too much stabilization(cement) will make no economic sense • Interlocking features do not provide air tightness. Minimum gap is formed due to which termite/air current can pass.

36. Limitations • Requires minimum mortar between the blocks to maintain horizontal construction level • Too much mortar between the blocks jeopardizes the interlocking feature • For frame structures, HI-CSEB can be used as filler materials but the structural members sizes increases due to increase in the block weight

37. HI-CSEB in Bhutan • No of private individuals who procured the machine-2 • Commercial basis- Established in Jemina by 2 firms

38. Way forward • Conference on GREEN Construction – Awareness and exchange of knowledge; 2. Sensitization w/shops & trainings in Green building practices; • Standards and regulations; • R & D required • Formulation of standards and guidelines

39. Conclusion • Sustainable /economical/eco friendly building material • Easy and simple technology • Creates employment opportunities • Reduce dependency on import of bricks • Making housing affordable Therefore, production and construction with HCSEB is relevant and it is to be adopted where ever possible.

40. Thank you and TashiDelek www. sqca.gov.bt