How Should I Insulate My Home in the Summer?
Installing insulation sounds like something you do in the autumn to prepare for winter in a northeastern state like Pennsylvania or New York. Kind of like squirreling away acorns for hibernation. But during the summer, you want to cool your home efficiently no matter where you live (though Texas residents have experienced extra-hot summers recently). Properly installed, energy efficient home insulation keeps the inside of your house comfortable all year long – just the right temperature and just the right humidity.
The less energy you use to keep your home comfortable and cool means the more money that you save on your electricity bills. Let’s examine the best steps for insulating your home to ward off the worst effects of the summer.
We’ve all heard the old saying, “Heat rises,” but technically, it’s only heated air that rises (convection). Heat (as energy) moves (conduction) through building materials like glass, wood, and concrete. Metal, for example, conducts heat much faster than wood. Once things get warm, it begins to radiate heat. In the winter, your home is a warm bubble that heat tries to radiate out from. In the summer, your home is a cool bubble that heat will radiate into. Energy efficient home insulation slows this process down and helps keep the heat where you want it.
There are many different kinds of insulation available for your home, and they’re all made from different materials with different insulating properties. For instance, thermal insulation is measured in “R” values for its heat transference resistance, which makes R-30 better than R-5. Generally speaking (depending on the material being used), the effects of thermal insulation are cumulative (to point). So if you add a layer of R-26 thermal insulation on top of already existing R-13 thermal insulation in your attic, you’ll have an R-39.
This amount of home insulation is very good at reducing any heat being conducted out from the house (in winter) or being conducted into the house (in summer). Because heat is conducted through wood, Sheetrock, brick, etc., insulation can be used in walls and floors.
As mentioned, not all home insulation has the same properties. Radiant barrier insulation (foil and bubble wrap), for example, has poor thermal insulation properties. However, it is installed in attics to keep these spaces cool and reduce air conditioning costs — especially when the duct work runs are located in the attic. When installed properly, radiant barriers can save homeowners in Texas or southern Florida up to $150 a year.
During the summer, the sun heats the roof. As the roof absorbs heat, it radiates this heat into the attic, heating up sheathing, rafters, joists, and also ventilation duct work. Radiant barrier insulation reduces heat flow, and by stapling it to the rafters on the roof slope facing the sun, it effectively reflects the radiant heat away from the rest of the attic. Radiant barrier insulation can also be wrapped around furnace duct work to make it more energy efficient — but spacers need to be attached to maintain an air space between the duct work and the radiant barrier insulation to maximize the efficiency. “Radiant barrier materials must have high reflectivity (usually 0.9, or 90%, or more) and low emittance (usually 0.1 or less), and must face an open air space to perform properly.”
With the right kind of home insulation, it will take less energy to keep your house comfortable. And the less your air conditioner has to work to keep you cool, the more money you’ll save off your electric bill. So, you shouldn’t wait until the winter winds start blowing before you start the insulating process. Whether you live in Texas, Pennsylvania, or New York, proper home insulation will save you money on your energy costs all year long.