The amount of energy your home demands is largely affected by the efficiency of the home envelope. The home envelope is the insulated structure that encloses your living space. Problems with the home envelope, such as having unseen air leaks, insufficient insulation, and low quality doors and windows translate into higher energy consumption.
LEAKS In the winter, more than any other time of the year, you will notice your home's air leaks. Most people call these air leaks "drafts." You may feel these drafts around windows and doors and think these leaks are your major source of wasted energy. In most homes, however, the most significant air leaks are hidden in the attic and basement. These are the leaks that significantly raise your energy bill and make the temperature in your home uncomfortable.
STOPPING THE CHIMNEY EFFECT In cold weather, warm indoor air rises throughout the home, just like a chimney, and sucks with it cold outdoor air through every crack and hole. This is called the chimney effect. Leaks in the attic increase the amount of outside air drawn in through basement cracks and holes. It is recommended that you seal openings that go through the basement ceiling to the floor above. Generally, these are holes for wires, water supply pipes, water drain pipes, plumbing vent pipes (for venting sewer gases), and furnace flues (for venting furnace exhaust).
The best material for sealing these hidden air leaks depends on the size of the gaps and their location. Caulk is best for cracks and gaps less than about 1/4" wide. Expanding foam sealant is an excellent material to use for sealing larger cracks and holes that are protected from sunlight and moisture. Backer rod or crack filler is a flexible foam material, usually round in cross-section (1/4" to 1" in diameter), and sold in long coils. Use it to seal large cracks and to provide a backing in very deep cracks that are to be sealed with caulk.
INSULATE Insulation is your primary defense against heat loss and air infiltration through the home envelope. Insulation is rated in terms of R-value or the resistance to heat transfer. The higher the R-value, the less heat transfer there is through a particular material. Insulations have high R-values, while materials like wood and concrete have very low R-values. This is why insulation is critical to your home envelope performance. Additionally, insulation is one of the most cost effective up-grades you can perform on your home.
Radiant barriers are another cost-effective energy solution for the attic. This can be achieved by installing a reflective barrier above the rafters prior to laying the wood sheeting or over your existing insulation to reflect the sun’s energy away from the attic space in the summer and retain radiant heat inside the house in the winter. With this method, an energy savings of 17% can be achieved, according to an Energy Star study.
Take a look at this chart, put out by the Department of Energy (DOE), of residential energy use for 2005. It gives you an idea of where to begin. Heating and cooling is 43% of the pie. You don't have to adjust the thermostat to use less energy; try installing an efficient Energy Star heating and cooling system. This will make the biggest energy reduction. Even changing the types of light bulbs in your home will reduce the amount of electricity used. Adding insulation to your structure, radiant barriers, and sealing up all the holes in your home are some of the most cost effective measures you can take to make your home more efficient.
We incorporate renewable energy and energy efficient system design custom for your home. Every home is unique and we feel that your home should be evaluated by an experienced professional. This will give you the greatest benefit.
