Sustainable Design for New Construction
Excellent tips from SolarWrights, a Rhode Island-based Solar Installation company, for anyone thinking about building sustainable and energy-efficient homes.
1. Site new homes so that you maximize the South wall. Minimize any roof protrusions such as pipes or dormers on the South roof to allow for the solar PV modules or solar thermal collectors. It is generally preferable to utilize a Gable roof design as opposed to a Hip roof.2. Keep the heated area of the home under 3,000 sq. ft. Use isolated solar sunspaces attached to the south wall of the heated portion of the home. See below for more information on passive solar sunspaces. Use air-lock entries to minimize heat loss when entering and exiting the home. Attach the garage to the North side of the home to provide a buffer against the cold North winds in the winter.
3. Maximize the utilization of direct gain passive solar energy through South-facing windows and glass doors by using South-facing windows and doors that have a SHGC (Solar Heat Gain Coefficient) of at least .50. A typical window with Insulated, Low-E coating has a SHGC of .30 meaning that only 30% of the solar energy makes it into home. Use moveable window insulation to boost the insulation value at night.
4. Utilize isolated solar sunspaces to maximize passive solar energy during sunny periods and to reduce heat loss from the adjoining house walls during cloudy days and nights. (For more information, see below)
5. Utilize solar energy or geothermal heat for heating your home and hot water needs. For space heating, collectors need to be tilted at 60 degrees to maximize winter solar gain and minimize summer overheating. For solar hot water systems only, tilt the collectors at 45 degrees.
6. Utilize photovoltaics or wind turbines to generate clean electricity for your home's electric needs. For grid-connected photovoltaic systems, mount the array at around 35 degrees to maximize annual electric production.
7. Purchase energy star appliances and lights for your home. Never install recessed lights in cathedral ceilings.
8. Minimize heat loss from the building envelop by maximizing the insulation of foundation walls, outside walls and attics and cathedral ceilings. Consider pre-cast foundations or ICF foundations for maximum insulation. Consider using ICF's or SIPS for upper walls. Timber framed homes with Stress-skin panels are also an excellent way to build. Don't use unhealthy insulation such as fiberglass in your home; consider blown-in icynene or cellulose insulation.
9. Utilize green building materials in the construction of your home.
10. Landscape your property with plants and lawns that are drought resistant and don't require the use of dangerous pesticides or chemicals such as dandelion killers.
