10 Ways to Keep Your Home Cool This Summer
(Bloomberg) -- To protect your home from floods and fire, you can raise the house out of harm’s way or establish an ember-resistance zone around the dwelling. But how do you safeguard your home against extreme heat, an increasingly frequent climate-driven threat that now strikes historically temperate regions?
“Even here, it's definitely a leading concern,” says Chris Magwood, who’s an Ontario, Canada-based sustainable construction expert for RMI, a nonprofit that promotes decarbonization.
If you’re building a new house, you can bake heat-resilience into the structure, while existing homes can be retrofitted with temperature-reducing features. Here are some of the most effective steps you can take to keep your home cool.
Cool down roofs and walls
A lighter color is better when it comes to a home’s roof and walls. The material doesn’t matter – a “cool roof” (1) can be made of asphalt shingles, metal or tile — as long as it’s light-colored so it reflects solar radiation away from the house. Such roofs can lower indoor temperatures from 2.2F to 5.9F (1.2–3.3C), according to the US Environmental Protection Agency.
Cool walls (2) are painted a light color or are covered by light-colored siding. Some paints are made with ingredients that reflect non-visible infrared radiation, which allows homeowners to use darker or more vibrant colors.
“A solar-reflective wall can go a long way to preventing heat from entering the building,” says Audrey McGarrell, communications manager for the Cool Roof Rating Council, a nonprofit in Portland, Oregon. “Cool roofs and cool building exteriors are really low-hanging fruit in terms of something that you can do to instantly improve the resilience of your home.”
Insulate the walls
Magwood lives in a straw-bale house he built. “It's 38 degrees Celsius [100F] outside right now, but I'm really nice and cool,” he says from Ontario. Traditional straw-bale homes (3) are built by plastering stacked straw bales. It’s more common now, though, for straw to be the insulating material in prefabricated wall panels.
The thick straw and plaster keep heat at bay. “It actually takes a fair bit of thermal energy to warm up that plaster skin to the point where heat is starting to transfer through the insulation and into the building, and, by then it's night,” says Magwood. On really hot days, Magwood’s heat pump, which also cools the home, will kick on, but not until the late afternoon, as the house stays at a comfortable temperature for most of the day.
Throw some shade
New construction should feature oversized eaves (4) to shield south and west-facing windows from the sun in the summer. Installing double-or-triple-paned glass and reducing the size of windows (5) that face the afternoon sun also will help lower temperatures
Adding a simple awning over sun-blasted windows also is effective, according to Magwood. “The house I grew up in New Hampshire was very uninsulated and the windows were terrible, but because of an awning we were able to keep the rooms a lot cooler,” he says. New windows are expensive so adding a solar-reflective coating to existing ones can help lower interior temperatures.
While shade trees and other landscaping (10) surrounding a home have cooling effects, in wildfire-prone areas, there may be restrictions on vegetation close to a house.
Have a backup plan
Heat pumps (6) are highly efficient electrical devices that ease demand on the power grid. However, in a widespread heat wave, utility blackouts can happen. A home battery (7) connected to rooftop solar panels can keep the electricity flowing to heat pumps and air conditioners. If you don’t have solar panels or a stationary energy-storage system, portable lithium-ion batteries can power fans and other devices.
Don’t forget the inside of your house
Putting up blackout curtains (8) or shades on sun-struck sides of a home can ease interior temperatures. Ceiling fans (9) keep air circulating and lower the strain on air conditioners and heat pumps.
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