Compared to a conventional house, a green house uses less energy, water and natural resources, creates less waste and provides a healthier environment for the people living there. A green home incorporates smart design, technology, construction and maintenance elements to lessen significantly the negative impact of the home on the environment and the health of the occupants and their neighbors. It also saves resources and money.
The U.S. Greenwich Building Council provides the following green home Guidelines:
New green homes and neighborhoods must not be built on environmentally sensitive sites like prime farmland, wetlands and endangered species habitats. Close proximity to public transportation–like bus lines and light rail that allows one to leave the car a home is a quality of green living. A green home would also be in close proximity to parks, schools and stores. In Greenwich there are many areas that would allow for this type of green living lifestyle.
No matter how many green building elements go into your home, a 5,000-square-foot green home still consumes many more natural resources than a 2,000-square-foot green home. The larger home will also require more heating, air conditioning and lighting. The smaller the size, the 'greener' it is.
The home should be oriented on its site to bring abundant natural daylight into the interior to reduce lighting requirements and to take advantage of any prevailing breezes. Windows, clerestories, skylights, light monitors, light shelves and other strategies should be used to bring daylight to the interior of the house. The exterior should have shading devices (canopies, green screens and–best of all–trees), particularly on the southern and western facades and over windows and doors, to block hot summer sun. Dual-glaze windows reduce heat gain in summer and heat loss during cold winter months. To reduce heat absorption, the roof should be a light-colored, heat-reflecting Energy Star roof or a green (landscaped) roof.
Green Building Materials
A green home will have been constructed or renovated with healthy, non-toxic building materials and furnishings, like low- and zero-VOC (volatile organic compound) paints and sealants and non-toxic materials like strawboard for the sub-flooring. Wood-based features should come from rapidly renewable sources like bamboo. If tropical hardwoods are used, they must be certified by the Forest Stewardship Council. A green home uses salvaged materials like kitchen tiles and materials with significant recycled content.
A non-toxic insulation, derived from materials like soybean or cotton, with a high R (heat resistance) factor in a home’s walls and roof will help prevent cool air leakage in the summer and warm air leakage in the winter.
Windows and Doors
Windows and exterior doors should have ENERGY STAR® ratings and they should seal their openings tightly to avoid heat gain in summer and heat loss in winter.
A green home has energy-efficient lighting, heating, cooling and water-heating systems. Appliances should have ENERGY STAR® ratings. Renewable Energy. The home should generate some of its own energy with technologies like photovoltaic systems.
A green home has a water-conserving irrigation system and water-efficient kitchen and bathroom fixtures. Look for a rainwater collection and storage system, particularly in drier regions where water is increasingly scarce and expensive.
Indoor Environmental Quality
Natural daylight should reach at least 75 percent of the home’s interior. Natural ventilation (via building orientation, operable windows, fans, wind chimneys and other strategies) should bring plentiful fresh air inside the house. The HVAC (heating, ventilation and air conditioning) system should filter all incoming air and vent stale air outside. The garage should not have any air handling equipment or return ducts, and it should have an exhaust fan.
Vine-covered green screens, large canopy trees and other landscaping should shade exterior walls, the driveway, patios and other so-called hardscape to minimize heat islands. Yards should be landscaped with drought-tolerant plants rather than water-guzzling plants and grass in most regions.