Green building is the practice of increasing the efficiency of buildings and their use of energy, water, and materials, and reducing building impacts on human health and the environment, through better siting, design, construction, operation, maintenance, and removal — the complete building life cycle.
A similar concept is natural building, which is usually on a smaller scale and tends to focus on the use of natural materials that are available locally. Other commonly used terms include sustainable design and green architecture; however, while good design is essential to green building, the actual operation, maintenance, and ultimate disposal or deconstruction of the building also have very significant effects on buildings' overall environmental impact.
The related concepts of sustainable development and sustainability are integral to green building. Effective green building can lead to 1) reduced operating costs by increasing productivity and using less energy and water, 2) improved public and occupant health due to improved indoor air quality, and 3) reduced environmental impacts by, for example, lessening storm water runoff and the heat island effect. Practitioners of green building often seek to achieve not only ecological but aesthetic harmony between a structure and its surrounding natural and built environment. The appearance and style of sustainable homes and buildings can be nearly indistinguishable from their less sustainable counterparts.
Green building is increasingly governed and driven by standards, such as the Leadership in Energy and Environmental Design (LEED) rating system developed by the U.S. Green Building Council.
Air pollution control
Air pollution dispersion modeling
Alternative energy
Biofuel
Composting
Conservation biology
Conservation ethic
Ecoforestry
Energy conservation
Energy development
Environmental design
Environmental impact assessment
Environmental preservation
Green building
Hydrogen technologies
Industrial wastewater treatment
Natural building
Recycling
Renewable energy
Renewable energy development
Remediation
Solid waste treatment
Sustainable architecture
Sustainable energy
Sustainable development
Waste water treatment
Water purification
Waste management The environmental impact of buildings
Green building brings together a vast array of practices and techniques to reduce and ultimately eliminate the impacts of buildings on the environment. On the aesthetic side of green architecture or sustainable design is the philosophy of designing a building that is in harmony with the natural features and resources surrounding the site. There are several key steps in designing sustainable buildings: specify 'green' building materials from local sources, reduce loads, optimize systems, and generate on-site renewable energy.
Building materials typically considered to be 'green' include rapidly renewable plant materials like bamboo and straw, lumber from forests certified to be sustainably managed, stone, recycled metal, and other products that are non-toxic, reusable, renewable, and/or recyclable. Building materials should be extracted and manufactured locally to the building site to minimize the energy embedded in their transportation.
Low-impact building materials are used wherever feasible: for example, insulation may be made from low VOC (volatile organic compound)-emitting materials such as recycled denim, rather than the insulation materials that may contain carcinogenic or toxic materials such as formaldehyde. To discourage insect damage, these alternate insulation materials may be treated with boric acid. Organic or milk-based paints may be used.
Architectural salvage and reclaimed materials are used when appropriate as well. When older buildings are demolished, frequently any good wood is reclaimed, renewed, and sold as flooring. Many other parts are reused as well, such as doors, windows, mantels, and hardware, thus reducing the consumption of new goods. When new materials are employed, green designers look for materials that are rapidly replenished, such as bamboo, which can be harvested for commercial use after only 6 years of growth, or cork oak, in which only the outer bark is removed for use, thus preserving the tree. When possible, building materials may be gleaned from the site itself; for example, if a new structure is being constructed in a wooded area, wood from the trees which were cut to make room for the building would be re-used as part of the building itself.
To minimize the energy loads within and on the structure, it is critical to orient the building to take advantage of cooling breezes and sunlight. Daylighting with ample windows will eliminate the need to turn on electric lights during the day (and provide great views outside too). Passive Solar can warm a building in the winter - but care needs to be taken to provide shade in the summer time to prevent overheating. Prevailing breezes and convection currents can passively cool the building in the summer. Thermal mass stores heat gained during the day and releases it at night minimizing the swings in temperature. Thermal mass can both heat the building in winter and cool it during the summer. Insulation is the final step to optimizing the structure. Well-insulated windows, doors, and walls help reduce energy loss, thereby reducing energy usage. These design features don't cost much money to construct and significantly reduce the energy needed to make the building comfortable.
Optimizing the heating and cooling systems through installing energy efficient machinery, commissioning, and heat recovery is the next step. Compared to optimizing the passive heating and cooling features through design, the gains made by engineering are relatively expensive and can add significantly to the projects cost. However, thoughtful integrated design can reduce costs -- for example, once a building has been designed to be more energy-efficient, it may be possible to downsize heating, ventilation and air-conditioning (HVAC) equipment, leading to substantial savings. To further address energy loss hot water heat recycling is used to reduce energy usage for domestic water heating. Ground source heat pumps are more energy efficient then other forms of heating and cooling until you factor in the energy lost during generation and transmission if the project is on the grid.
Finally, onsite generation of renewable energy through solar power, wind power, hydro power, or biomass can significantly reduce the environmental impact of the building. Power generation is the most expensive feature to add to a building.
Good green architecture also reduces waste, of energy, water and materials. During the construction phase, one goal should be to reduce the amount of material going to landfills. Well-designed buildings also help reduce the amount of waste generated by the occupants as well, by providing onsite solutions such as compost bins to reduce matter going to landfills.
To reduce the impact on wells or water treatment plants, several options exist. "Greywater", wastewater from sources such as dishwashing or washing machines, can be used for non-potable purposes, e.g., to flush toilets, water lawns, and wash cars. Rainwater collectors are used for similar purposes, and some homes use specially designed rainwater collectors to gather rainwater for all water use, including drinking water.
Green building often emphasizes taking advantage of renewable resources, e.g., using sunlight through passive solar, active solar, and photovoltaic techniques and using plants and trees through green roofs, rain gardens, and for reduction of rainwater run-off. Many other techniques, such as using packed gravel for parking lots instead of concrete or asphalt to enhance replenishment of ground water, are used as well.
Green building practices
Green building worldwide
Many countries have developed their own standards of energy efficiency for buildings.
Code for Sustainable Homes, United Kingdom
BREEAM, United Kingdom
EnerGuide for Houses, Canada (energy retrofits & up-grades)
EnerGuide for New Houses, Canada (new construction)
Gold & Silver Energy Standards, United Kingdom
Green Building Council of Australia's Green Star
Haute Qualité Environnementale, France
House Energy Rating, Australia
Leadership in Energy and Environmental Design (LEED), USA and Canada
Green Globes, USA, Canada and United Kingdom
Minergie, Switzerland
National Association of Home Builders Green Building Guidelines, USA
New Zealand Green Building Council Green Star
Passivhaus, Germany, Austria, United Kingdom
EEWH, Taiwan Standards and ratings
There is a system in place in Australia called First Rate designed to increase energy efficiency of residential buildings. The Green Building Council of Australia (GBCA) has developed a green building standard known as Green Star..
In Adelaide, South Australia, there are at least two different projects that incorporate the principles of Green building. The Eco-City development is located in Adelaide's city centre and the Aldinga Arts Eco Village is located in Aldinga. Guidelines for building developments in each project are outlined in the bylaws. The bylaws include grey water reuse, reuse of stormwater, capture of rainwater, use of solar panels for electricity and hotwater, solar passive building design and community gardens and landscaping.
Melbourne has a rapidly growing environmental consciousness, many government subsidies and rebates are available for water tanks, water efficient products (such as shower heads) and solar hot water systems. The city is home to many examples of green buildings and sustainable development such as the CERES Environmental Park. Two of the most prominent examples of green commercial buildings in Australia are located in Melbourne - 60L and Council House 2 (also known as CH2).
Australia
Canada has implemented "R-2000" guidelines for new buildings built after the year 2000. Incentives are offered to builders to meet the R-2000 standard in an effort to increase energy efficiency and promote sustainability.
A progression of the R-2000 home program is the EnerGuide for New Houses service. This service is available across Canada and is designed to allow home builders and home buyers to build homes that use significantly less energy than the average homes being built. Some Canadian provinces are considering mandatory use of the service for all new homes.
In December 2002, Canada formed the Canada Green Building Council and in July 2003 obtained an exclusive licence from the US Green Building Council to adapt the LEED rating system to Canadian circumstances.
Beamish-Munro Hall at Queen's University features sustainable construction methods such as high fly-ash concrete, triple-glazed windows, dimmable fluorescent lights and a grid-tied photovoltaic array.
Gene H. Kruger Pavilion at Laval University uses largely non polluting, non toxic, recycled and renewable materials as well as advanced bioclimatic concepts that reduce energy consumption by 25% compared with a concrete building of the same dimensions. The structure of the building is made entirely out of wood products, thus further reducing the environmental impact of the building. Canada
German developments that employ green building techniques include:
The Solarsiedlung (Solar Village) in Freiburg, Germany, which features energy-plus houses.
The Vauban development, also in Freiburg.
Houses designed by Baufritz, incorporating passive solar design, heavily insulated walls, triple-glaze doors and windows, non-toxic paints and finishes, summer shading, heat recovery ventilation, and greywater treatment systems.
The new Reichstag building in Berlin, which produces its own energy. Germany
Main article: Energy efficient buildings in India
The Confederation of Indian Industry plays an active role in promoting sustainability in the Indian construction sector. There are many energy efficient buildings in India, situated in a variety of climatic zones.
India
The Standards and Industrial Research Institute of Malaysia (SIRIM) promotes green building techniques. Malaysian architect Ken Yeang is a prominent voice in the area of ecological design.
Malaysia
The New Zealand Green Building Council has been in formation since July 2005. An establishment board was formed later in 2005 and with formal organisational status granted on 1st February 2006. That month Jane Henley was appointed as the CEO and activity to gain membership of the World GBC began. In July 2006 the first full board was appointed with 12 members reflecting wide industry involvement. The several major milestones were achieved in 2006/2007; becoming a member of the World GBC, the launch of the Green Star NZ - Office Design Tool, and welcoming our member companies.
New Zealand
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