The Do’s and Don'ts of Attic Ventilation

By: Ed Fritz

Most likely, your attic is one part of your home you very seldom think about. Out of sight, out of mind. Unfortunately, NOT thinking about your attic, and especially how it is ventilated, can be a costly mistake. If your attic isn’t properly ventilated, you can find your energy bills increasing drastically, especially during the warmer months. Allowing heat trapped in your attic to escape efficiently can do a great deal to cool your entire home. Unfortunately, too many people make some pretty basic mistakes when it comes to ventilating their attic. Here are some things you should and shouldn’t do.

DO take a close look at the condition of your existing soffit vents. These are the holes in the bottom of your attic that draw the air in. A great many homeowners will find that these vents have never once been inspected, let alone cleaned. Often, vents will have been painted over or are clogged in some other way. They can be easily cleaned with a nylon car wheel brush. Also make sure that the hole behind the vent is large enough to be effective. Sometimes vents are installed and closer inspection shows that there is no hole behind them at all! Once your soffit vents are clear, exhaust vents that may have been working poorly or not at all may start working right away, since they once again have air moving through them.

DO think about installing a radiant barrier. A properly ventilated attic will do a lot to decrease the air temperatures within, but the roof itself can still absorb a great deal of heat. A radiant barrier will maximize efficiency by minimizing surface temperature of the attic insulation

DON’T get carried away with installing a large number of vents all over your roof. The whole point of attic ventilation is to pull air in from below and expel it through the top. Too many vents will pull air away from each other, rather than from the whole attic. The area near the vents will be well-ventilated, but the rest will remain stagnant. The stronger vent will dominate, possibly turning any others near it into intake vents, which of course defeats the purpose of having them there in the first place.

Also, DON’T mix and match your vents. Since a variety of vents are available- wind turbines, power fans, ridge vents, or static vents- many homeowners think using all of them is best. Again, since the strongest vents will pull the most air out, the weaker ones could pull it in. For example: a power fan installed next to a ridge vent will just pull air in through the ridge vent rather than the lower soffit vents.

This leads to the big DO of attic ventilation: pick one type of exhaust vent and go with it. Make sure all of these vents are installed near the top of your roof and within a few feet of each other. If your soffit vents are functioning properly, air should flow freely into your attic from below, and right out the top.

Attic ventilation doesn’t need to be complicated. Just remember that hot air rises, and providing it with properly placed vents means it can do what it was meant to do more efficiently, leaving your attic cooler in the summer and drier in the winter.