Green building is the practice of increasing the efficiency with which buildings and their sites use and harvest energy, water, and materials, and reducing building impacts on human health and the environment, through better sitting, design, construction, operation, maintenance, and removal — the complete building life cycle.
Green building is also sometimes known as sustainable building or environmental building, although there are slight differences in the definitions. The practice of green building can lead to benefits including reduced operating costs by increasing productivity and using less energy and water, improved public and occupant health due to improved indoor air quality, and reduced environmental impacts by, for example, lessening storm water runoff and the heat island effect.
Green building is an essential component of the related concepts of sustainable design, sustainable development and general sustainability.
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.
Sustainable building techniques
Green building and natural building are both sets of building techniques that aim to be more sustainable than conventional construction. However, there is a difference in degree of sustainability. In practice, green building tends to be popular with professionals in the development industry who are convinced that building more sustainably is not only necessary to lessen impact on the environment, but also makes good economic sense. Green building is increasingly governed by standards, such as the Leadership in Energy and Environmental Design (LEED) standards developed by the U.S. Green Building Council. Natural building, on the other hand, is usually on a smaller scale and tends to focus on the use of natural materials that are available locally.
Main article: Green architecture
The focus of green architecture is for the project to work in harmony with the natural features and resources surrounding the site, and to use materials that are sustainably grown or recycled rather than new materials from non-renewable resources.
Building materials may be sought within a 500-mile radius of the building site to minimize the use of fuel for transportation. The building itself may be oriented a particular direction to take advantage of naturally occurring features such as wind direction and angle of the sun. 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. Taking advantage of available natural light reduces dependence on artificial (energy-using) light sources. Well-insulated windows, doors, and walls help reduce energy loss, thereby reducing energy usage. To further address energy loss hot water heat recycling is used to reduce energy usage for domestic water heating.
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 fiberglass insulation which is dangerous to breathe. To discourage insect damage, the insulation 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.
Good green architecture also reduces waste, of both energy and material. During construction phase, the goal is 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 treatments plants, several options exist. “Greywater“, wastewater from sources such as dishwashing or washing machines, can be used 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 architecture 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 worldwide
Standards and ratings
Many countries have developed their own standards of energy efficiency for buildings.
- Code for Sustainable Homes, 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
- Passivhaus, Germany, Austria, United Kingdom
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 the 60L and CH2 buildings in Melbourne.
Canada has implemented “r2000” guidelines for new buildings built after the year 2000. Incentives are offered to builders to meet the r2000 standard in an effort to increase energy efficiency and promote sustainability. 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.
German developments that employ green building techniques include:
- 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.
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, situtated in a variety of climatic zones.
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.
Main article: Energy efficiency in British housing
The Association for Environment Conscious Building (AECB) has promoted sustainable building in the UK since 1989.
The United States Green Building Council (USGBC) has developed The Leadership in Energy and Environmental Design (LEED) Green Building Rating System™, which is the nationally accepted benchmark for the design, construction, and operation of high performance green buildings. LEED gives building owners and operators the tools they need to have an immediate and measurable impact on their buildings’ performance. LEED promotes a whole-building approach to sustainability by recognizing performance in five key areas of human and environmental health: sustainable site development, water savings, energy efficiency, materials selection, and indoor environmental quality. They have developed specific versions of the LEED rating system to assist specific building types in achieving certification. Some of the commercially available systems are:
- LEED-NC: New Construction and Major Renovations (the most commonly applied-for LEED certification)
- LEED-CI: Commercial Interiors
- LEED-CS: Core/Shell)
- LEED-EB: Existing Buildings
Other versions that will soon be released for public consumption are:
- LEED-ND: Neighborhood Developments
- LEED for Schools
- LEED for Healthcare
- LEED for Labs
- LEED for Retail
The Green Building Initiative is a non-profit network of building industry leaders committed to bringing green to mainstream residential and commercial construction. The GBI believes in building approaches that are environmentally progressive, but also practical and affordable for builders to implement. The GBI has developed an easy to use, inexpensive and web-based rating tool called Green Globes, which is being upgraded in accordance with ANSI procedures.
The United States Environmental Protection Agency‘s EnergyStar program rates commercial buildings for energy efficiency and provides EnergyStar qualifications for new homes that meet their standards for energy efficient building design.
In 2005, Washington became the first state in the U.S. to enact green building legislation. According to the law, all major public agency facilities with a floor area exceeding 5,000 square feet (465 m²), including state funded school buildings, are required to meet or exceed LEED standards in construction or renovation. The projected benefits from this law are:
- 20% annual savings in energy costs
- 20% reduction in water costs
- 38% reduction in waste water production
- 22% reduction in construction waste
In 2006, Charlottesville, VA became one of the first small towns in the US to enact green building legislation. This presents a significant shift in construction and architecture as LEED regulations have formerly been focused on commercial construction. If US homeowner interest grows in “green” residential construction, the companies involved in the production and manufacturing of LEED building materials will become likely candidates for tomorrow’s round of private equity and IPO investing.