Winter conjures images of snuggling in front warm fires, thick sweaters, colder temperatures and maybe even snow outside. For many air-sealers and insulators, winter’s when the phone starts ringing, and busy season hits – when people feel frigid drafts in their homes and decide it’s time to add more insulation.
By Contributing Writer, Melissa Baldridge, GreenSpot
But summer is when it makes more sense economically to air-seal and insulate your attic because cooling costs (running your electrically powered air-conditioner) hit harder than heating costs (using your gas-powered furnace to heat your home). A better way to think of attic insulation is like a barrier between your living spaces and the super-heated outside, rather than just a fleece layer you add to your house when the weather turns chilly.
Summer sun heats up roof decks to temperatures as high as 140 degrees (F), or higher in many parts of the country. That temperature is enough to slow-cook meat, and it can drag on for hours a day, from June until well into fall. Those super-heated roof decks and attics are contiguous to living spaces we all pay dearly to cool to 70-something degrees. The temperature difference between inside and the upper reaches of your home can be close to 100 degrees for months on end.
Heating and cooling specialists design home heating and cooling systems to handle worst-case scenarios. Here in Denver, that wintertime doomsday temp is 4 degrees below zero, which we hit three to four nights a year. In more temperate parts of the country, the bottom-line number is higher. But those frigid days and nights are fewer and farther between so heating systems don’t run full-tilt-boogie for hours, weeks and months like air-conditioners do.
Electricity also costs more than gas. And refrigerated cooling systems cost more to operate per unit of power (BTU) than gas-powered heating systems. Many utility providers even charge different rates per kilowatt hour (unit of electricity over time) at different times of day. In many parts of the country if you use more than a certain number of kilowatt hours, your utility company socks it to you in the form of a price premium for the additional power. These “demand charges” can add up quickly, and many homeowners get sticker shock when they see what it costs to chill out.
There are other ways you can cool the spaces in and around your house. Passive attic ventilation is one example. As air enters your attic through soffit vents at the roof eave, “spot” or ridge-top vents pull that hot air out. Also “radiant barriers” (foil-faced layers) bounce the sun’s heat out of your house. How that’s installed (where the foil face aims) will vary depending on where you are in the country. Beware – radiant barriers are worthless when installed improperly. Trustworthy roofing professionals can help you sift through false claims about them.
If your house heats up like an oven in the summer, NOW’S the time to add insulation. Don’t wait for fall – insulate to beat summer heat. Your house will feel better, and your cooling bills will be lower.