You’ve swapped your incandescent lightbulbs for compact fluorescents, turned down your water heater, and set up your programmable thermostat. These are all good moves toward saving energy in your home, but what else can you do? Builders, architects, and building scientists know lots of tricks for lightening the energy load on our homes, some of them expensive and complicated, but many more simply a matter of taking a second look at what’s already in place. If you’re ready to put a few more check marks on that energy-saving scorecard, here are 25 strategies that can take you to the next level.
Get some help from the sun
The sun can help to warm a house in winter, especially when the south side of the house is unshaded from about 9 a.m. until 3 p.m. In northern climates, keeping trees far enough from the south side of the house so that they don’t cast a shadow allows more light—and heat—inside. Deciduous trees can interfere with solar gain even when their leaves are gone. To improve solar gain, it may be necessary to trim trees or even remove them. If the house has photovoltaic panels, keeping shade off south-facing roofs is essential. Removing trees close to the house also reduces the risk of trapped moisture, mold, and decay. Don’t, however, remove shade trees on east- and west-facing sides of the house; this can cause overheating in summer.
Use outdoor air to heat and cool
Effective natural ventilation can reduce the need for air-conditioning and can even aid in heating under some circumstances.
A house designed for cross ventilation will get the most out of natural cooling, but you can encourage air movement in any home. When the air outside is pleasant, open a window on the downwind side to allow hot indoor air to be pulled from the house, and open a window on the upwind side to allow cooler outdoor air in. It’s also possible to introduce fresh air with a mechanical ventilation system, such as a fan.
In a heating climate, make sure the supply air for your ventilation system is drawn from the warm, sunny side of the house. In a cooling climate, draw supply air from a cool, shady area. In all climates, ventilation air should be drawn from areas that aren’t susceptible to low air quality. Avoid placing supply vents near dryer vents or parking lots.
Shade south-facing windows
The sun can easily overwhelm a house in summer. Exterior louvers, trellises, or awnings help to shade your windows, keeping the house cool. Louvers are preferable to awnings because they do a better job of shading windows when the sun is at a low angle or from the side; they also provide a partial view through the window. Trellises also can be used to shade windows from direct sunlight. Using one of these features may allow your house to have a smaller air conditioning system.