Buildings account for one-sixth of the world’s fresh water withdrawals, one-quarter of its wood harvest and two-fifths of its material and energy flows. The type of buildings which are constructed by incorporating tripod of attributes; energy efficiency (both in material selection and actual energy use), healthy living including indoor air quality, and careful resource management are termed as Green Buildings. Green building does not require any architectural style which looks visually green. It doesn’t have to be expensive to build, nor does it have to look “different”. It can be designed in any style, or any shape. The main focus of green building is to provide benefits to the occupants. These include: Less expensive to heat and cool, Greater comfort, Healthier, particularly for children, Greater durability and less maintenance. A green building, also known as a sustainable building, is a structure that is designed, built, renovated, operated, or reused in an ecological and resource-efficient manner. Green buildings are designed to meet certain objectives such as protecting occupant health; improving employee productivity; using energy, water, and other resources more efficiently; and reducing the overall impact to the environment. The different aspects of green building constructed for sustainable development are described here.
Buildings are very complex system comprises different subsystem in which every component has got a strong interaction with other and hence affects the structure as a whole. Each component of building is made up of individual products, different technologies which in turn dictate the function of the products, particularly the relationships amongst the different components. The building can be considered as an analogous system of human body which comprises different parts but we see the cumulative effect of the parts as a whole and are reflected in the body. Human bodies comprise various subsystems viz. a cooling system, a heating system, digestive system and a waste disposal system which require energy. All these systems work together and provides the best performance of the human body. In order to maintain the health and comfort of a human being, body must be capable of cooling down when it is hot, heat up when it is cool and disposal of waste. In order to maintain equilibrium of the system we need energy so is the case with the buildings where we live. All the activities performed by human body are required for a building like breathing means circulation of air in a building, and as well as heating and cooling of the building (either natural or artificial). This analogy, if we can apply properly for the design and layout of building components then the building will cause minimum or no damage to the environment and hence be a sustainable construction. The building envelope (i.e. walls and roof) acts like skin of human body and hence the most crucial parts of the building. It regulate the inside temperature and overall condition of the building and is directly related to the inside outside interaction of the building. Building should be capable of utilizing the benefits obtained from the surrounding environment. Building plans should be able to reflect their surroundings and the varied climatic conditions. As the nature’s characteristics affect the human being so is the case for building. The different elements of a Green building are described below:
Location: The building construction site is well suited to take advantage of mass transit facilities. The natural landscaping and natural features should not be destructed as far as possible so that the advantage out of these natural features can be explored properly. Use of plantation which needs low water and less pesticide are very important component of a green building and plants should require fewer trimmings. Organic fertilizer like compost and mulches should be used and chemical fertilizer should be avoided as far as possible. This will save water and time. Recycled content paving materials, furnishings, and mulches help close the recycling loop.
Energy Efficiency: Building consumes energy mainly for cooling, heating and lightening. The design of a building should be such that it can use maximum available energy of the nature and this type of design is termed as Passive Design of a Building. Passive Design of building can dramatically change the energy use pattern of a building. The measures include building shape and orientation, passive solar design, and the use of natural lighting. Studies have proved that this type of design has a positive impact on productivity and well being. Install high-efficiency lighting systems with advanced lighting controls. Include motion sensors tied to dimmable lighting controls. Task lighting reduces general overhead light levels. Use a properly sized and energy-efficient heat/cooling system in conjunction with a thermally efficient building shell. Maximize light colors for roofing and wall finish materials; install high R-value wall and ceiling insulation; and use minimal glass on east and west exposures. Minimize the electric loads from lighting, equipment, and appliances. Use of renewable energy provides a great symbol of emerging technologies for the future.
Materials Efficiency: Selection of new construction materials and use of recycled and scrap materials are the two important factors for the construction of Green buildings. Such products promote resource conservation and efficiency. Using recycled-content products also helps in Solid Waste Management system. Use dimensional planning and other material efficiency strategies. These strategies reduce the amount of building materials needed and cut construction costs. Reuse and recycle construction and demolition materials. For example, using inert demolition materials as a base course for a parking lot keeps materials out of landfills and costs less.
Occupant Health and Safety: Research findings reported in different literatures revealed that buildings with good overall environmental quality can reduce the rate of respiratory disease, allergy, asthma, sick building symptoms, and enhance worker performance. Choose construction materials and interior finish products with zero or low emissions to improve indoor air quality. Many building materials and cleaning/maintenance products emit toxic gases, such as volatile organic compounds (VOC) and formaldehyde. These gases can have a detrimental impact on occupants’ health and productivity. Provide adequate ventilation and a high-efficiency, in-duct filtration system. Heating and cooling systems that ensure adequate ventilation and proper filtration can have a dramatic and positive impact on indoor air quality. Prevent indoor microbial contamination through selection of materials resistant to microbial growth, provide effective drainage from the roof and surrounding landscape, install adequate ventilation in bathrooms, allow proper drainage of air-conditioning coils, and design other building systems to control humidity.
Water Efficiency: Economic use of water is one of the prime criteria for Green building. The recycled water can be used for toilet flushing or other non potable use like water for plants and trees. Rainwater harvesting should be opted for non potable use for optimum use of water sources which consumes energy and causes extra heat to the environment. Green building concept of building design cannot achieve their goals unless they work as intended. Building commissioning does not merely mean the testing and adjusting the mechanical, electrical, and plumbing systems to meet design criteria but also includes instructing the staff on the operation and maintenance of equipment.
Use of Green Building Materials: The use of materials in construction should be so selected that it gives minimal environmental impact to the nature. The materials used as a green material not necessarily are green in colour but it should have those properties which help to keep our surroundings. 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
- Improved occupant health and productivity
- Lower costs associated with changing space configurations
- Greater design flexibility
Use of Scrap and Recycled aggregate: Although the use of scrap and recycled materials are not allowed in India till today due to lack of standards but in the developed countries it is very much encouraged now due to huge dumping problem. The Condominium complex in Humberg was constructed with recycled aggregate 50 years ago and is in good condition.
Benefits of Green Building: In short in can be concluded that the potential benefits obtained from green building can be summerised as follows:
- Enhance and protect ecosystems and biodiversity
- Improve air and water quality
- Reduce solid waste
- Conserve natural resources
- Reduce operating costs
- Enhance asset value and profits
- Improve employee productivity and satisfaction
- Optimize life-cycle economic performance
Health and Community Benefits
- Improve air, thermal, and acoustic environments
- Enhance occupant comfort and health
- Minimize strain on local infrastructure
- Contribute to overall quality of life
- Going Green is ‘future-proofing’ your asset
- Bora, Mukul Chandra (2009). “Land use, Climate Change and its Impact on Water resources”, on Proceedings, International Seminar on Water Crisis in the Indian Sub Continent: Issues and Challenges, 23-24th November, 2009, North Eastern Hill University, Shillong, Meghalaya, India
- Bora, Mukul Chandra. “Sustainable Construction with People Participation” The Second International Conference on Sustainable Architecture and Urban Development 12- 14 July, 2010, Amman, Jordan (Accepted).
- Bora, Mukul Chandra. “Development in Transportation Sector - Sustainability with Scrap, Recycled and Biodegradable Materials” 8th Malaysian Road Conference 10-13th October 2010, Towards Sustainable Road Development and Operations. (Accepted)
- Bora, Mukul Chandra (2010) “Growth of Infrastructure and Climate Change in Guwahati City”, In Proc. International Conference on Infrastructure Finance, June.2-5, 2010, IITKharagpur, West Bengal, India
- Bora, Mukul Chandra. “Waste tyres management and its use in Transportation,” International Conference on Infrastructure, Sustainable Transportation and Urban Planning to be held from 18-20th October, 2010 at IIScBangalore (Accepted)
- Bora, Mukul Chandra (2010). “Climate Change and its Impact on Ground Water” Proceedings, National Conference on Sustainable Water Resources Management and Impact of Climate Change, BITS-Pilani, Hyderabad, India from 5-6th March 2010
- Bora, Mukul Chandra (2010). “Changes in Land use - Its impact on climate change” In abstract of Proceedings, National Seminar on Climate Change and Sustainable Development with Reference to India to be held in Tezpur University, India from April 1-3, 2010