How to make your house more energy-efficient

Habitat for Humanity Greater Boston believes that green homes are great on many levels. Good for volunteers and friends to see green building in progress. Better for our community and environment. And best for our homeowners who live in healthier homes that cost less to occupy and maintain.

What we do

In the past six years, Habitat Greater Boston has built 43 new units and renovated eight homes.

• Our standard mechanical system is a high-efficiency condensing boiler with an integral on-demand domestic water heater.
• Insulation and air sealing are a critical component in the efficiency of our homes.
• All framing members are caulked at the floor (bottom plate), ceiling (top plate) and sheathing joints. Extra care is given to door and window openings.
• Windows are insulated, gas-filled, low-e glass in both our rehabs and new construction.
• Because of the tightness of our homes, we install at least one continuously operating extraction fan.
• All light fixtures and appliances are Energy Star-certified. Motion detector light switches are used on a case-by-case basis.

Our strategies might not be applicable to existing homeowners without significant capital costs. But there are steps that you can take to make your home operate more efficiently.

Tasks you can undertake

Perform an energy audit. Someone once said, “Before you begin a journey, it is imperative to know where you are.” Have an energy audit done on your home. Most utilities will help you secure an appropriate energy auditor, and most have programs to subsidize or underwrite the costs. If your local utility doesn’t have such a program, check with your municipality.

Replace your thermostat. In the old days, when heating oil was 28 cents a gallon, our parents would “set and forget” the thermostat. The temperature setting would not change until the seasons changed. Programmable thermostats — which are made to work with all types of heating and cooling equipment and range in cost from 45 to 120 — can be set to keep us comfortable when we need it (weekend days, evenings when the kids get home from school) and to use less fuel at other times (when we’re in bed, while we are at work or school).

Interrupt air movement. When it’s cold outside, we want to keep the warmth inside. When it’s hot outside, we want to keep our cool inside. Weather stripping and caulking are relatively low expenditures, relatively easy to install and can result in a significant increase in your comfort — and a decrease in your heating and cooling costs.

Clean your coils. Use the crevice head on your vacuum cleaner to remove the buildup of dust on your refrigerator’s evaporator coils. Dust acts like an insulation blanket, which causes the refrigerator to work harder and use more electricity. Keeping the coils clean reduces the amount of electricity used and prolongs the life of the equipment. The coils are usually located at the bottom of the appliance and are generally accessible behind the removable grill below the door.

Create shade. Solar heat gain is a wonderful source of “free” heat during the winter, but can make us uncomfortable in the heat of the summer. Awnings on south-facing windows are ideal, but sometimes impractical. Similar benefits can be derived from window shades or opaque curtains. Shades or curtains should be closed during the peak hours of 10 a.m. to 5 p.m. If you’re living without air conditioning, open your windows and shades after that to allow afternoon breezes to help cool the interior of your living space.

— George O’Malley, Habitat Greater Boston’s director of projects