Columbia Energy Efficiency Mythbusters: Should I Install an Attic Fan?

June 3, 2015 Written by  Comments Print
Rate this item
(0 votes)

There's a lot of good advice out there about how you can make your home more energy efficient and save money on your energy bills. In fact, you can find plenty of good tips right here in our blog!

Unfortunately, the Columbia energy efficiency myths just keep on coming. Good thing greeNEWit is here to bust them! Check out some of our previous blogs on whether you should turn off the A/C while you're away, or this two for one blog on windows and draft problems, and closing vents to save money on cooling costs.

This week's subject? Attic fans. You may have heard that installing an attic fan can help you pull hot air out of the attic, thereby cooling it down and reducing your air conditioning costs. Is this true? The short answer? No! The long answer? Read our blog to find out!

Columbia Energy Efficiency Mythbusters: Should I Install an Attic Fan?

What is an attic fan?

An attic fan, also known as a powered attic ventilator, is a fan mounted on the gable wall or sloped roof of your attic. They are controlled by a thermostat and turn on when the attic gets too hot.

The Myth

Here's the myth. The idea is that by running an attic fan, you can pull all that hot air out of the attic. This results in a cooler attic, which results in a cooler house, which reduces your cooling costs.

Sounds logical, right? Actually, only the first part is true. That attic fan will pull hot air out of the attic, but it will also do a couple things you don't want it to do.

The Facts

So yes, it's true that an attic fan pulls hot air out of the attic. But, here's what else happens when you try this Columbia energy efficiency myth:

Air is pulled into the attic from the house or outside.

When you pull air out of the attic with an attic fan, it creates a pressure imbalance in the attic. Now the attic is at a negative pressure compared to its surroundings. This causes air to flow into the attic either from the outdoors (if there are air leaks) or from your home. In one case, you're just replacing hot air with more hot air. In the other, you're replacing hot air with cool air that you paid for and would rather keep in a conditioned space. In either case, you're wasting money on running the attic fan, and your house isn't getting any cooler.

The Solution

Installing an attic fan won't make your home any cooler. Instead, the best course of action is:

  • Seal air leaks in the attic to prevent air from getting in.

  • Insulate the attic floor to reduce heat transfer from the attic into your home.

Want to learn more about Columbia energy efficiency strategies? Talk to greeNEWit! Call us today at 866.966.7630 or use our contact form to learn how a home energy audit can increase the energy efficiency of your home.

Check us out on Facebook and Twitter!