With the increased prices of heating oil, many homeowners have started weatherizing their homes, with encouragement from federal and state tax incentives and rebates. Weatherizing your home not only reduces heating costs, it reduces cooling costs.
Maine doesn’t get the blistering hot summers of other parts of the U.S., but we can get heat waves that cause a run on air conditioners in local stores. However, there are more cost-effective ways to keep comfortable in hot weather in Maine. There are a number of things we can do before hot weather gets here that will reduce the need for air conditioning and save money.
The sealing and insulating involved in weatherizing your home will not only keep the warm air in during winter; it can also help keep the hot air out in the summer. For instance, attic insulation protects you from the heat of the sun beating down on your roof, while eave and ridge vents give heat a pathway to rise up and out of the attic space.
In Maine in the summer, evening and early morning air temperatures are often dramatically lower than daytime temperatures. Take advantage of this temperature shift. Open windows and doors on opposite sides of the house, or position fans to bring in the cool evening or morning air. Once the coolness is gone, close up the house for the day. Keep the hot air outside. Take advantage of the wind-chill factor by using floor and ceiling fans to circulate a cooling breeze. Remember that most ceiling fans have a summer setting, so be sure to change the switch to summer.
Along with closing the windows and doors, draw the drapes to keep the sun from heating up rooms. Close east-side drapes or curtains first; then later close the south- and west-facing drapes. Once the sun has passed that side of the house you can reopen the drapes. Other options include exterior shutters, window awnings, or plastic films. Permanent plastic films should only be applied to east- or west-facing windows, because they will reduce the solar gain on the south-facing windows too much during the winter when you need the warmth.
Refrigerators and freezers pump heat into our living areas as they chill food, so open the doors of these appliances as little as possible to reduce the amount that the motor must run. If your refrigerator or freezer is more than 15 years old, a new energy-efficient model will pay for itself quickly in energy savings. In addition, there are rebates available for ENERGY STAR-rated appliances.
Other ways to keep your home cool include cooking outdoors whenever possible, and running washers, dryers, and dishwashers at night or early in the morning when it’s cooler. Use lights sparingly, since they, too generate heat. Dress for the weather: loose-fitting light-weight shorts and short-sleeved shirts will be more comfortable.
Planting trees in your landscape now will provide great energy savings in the future, in both summer and winter. The U.S. Department of Energy (DOE) estimates that “shading your home can reduce indoor temperatures by as much as 20°F.” For summer cooling, plant small-to medium-height deciduous shade trees near the east- and west-facing walls of your house. Deciduous trees shed their leaves in the fall, allowing winter sun to warm your home. To shade the roof, plant taller deciduous trees in the southwest and southeast corners of your yard, but keep the true south side of your house tree-free to get all the solar gain possible during the winter. Place large trees no closer to your house than 20 feet.
The DOE also found that a grass-covered lawn is usually 10°F cooler than bare ground in the summer. Growing grass or ground covers will help keep your home cooler than surrounding it with asphalt, concrete, or bare dirt. Ground covers or slow-growing grasses don’t need to be mowed, watered, or fertilized as often as a fast-growing grass, and will save you more energy.
Planting a thick line of evergreen trees 40 to 100 feet from your house to block the cold northwesterly winds, as well as placing evergreen foundation plantings about five feet from the house to create a “dead air” space, will help reduce your winter heating costs. Windbreaks can reduce winter fuel consumption by 10 to 30 percent. Fences and trellises with climbing plants can provide wind and shade while you are waiting for your trees to grow. The DOE estimates that just three properly placed trees can save an average household $100 to $250 in heating and cooling energy costs annually.
If you still need cooling during extremely hot weather, consider one of these two options:
- An evaporative cooler, which uses less energy than an air conditioner and delivers cool, damp air to your living space
- An energy-efficient air conditioner that is sized to the space you need to cool. Install window air conditioners snugly and insulate for a tighter fit. Place air conditioners in a shady location if possible. Planting shade-casting plants around the conditioner keeps the surrounding air cooler, so the appliance doesn’t have to work as hard.