Determining If Your Home Needs Attic Ventilation Fans

blankWhen you’re suffering through a heat wave, you probably don’t stop to think about your attic. This is the last place you want to go when it’s hot outside, but you shouldn’t neglect it either. After all, your attic shields your home against the heat. As such, it has a major impact on how hot the rest of your home will get and whether you must run your air conditioner more. By improving your attic’s ventilation and reducing how much heat is held there you can save money on your electric bill. As you stop to consider this, you should consider installing attic fans.

How They Work

Attic fans work by pushing out the hot air that stores up inside your attic and bringing in cool, outdoor air. This will prevent hot air from entering your home where it’ll increase the temperature and the load on your air conditioner.

Most homes already have some venting and roof insulation built into them. This is in the form of soffit vents that are built into the eaves where they can bring cool air into your home. There are also roof gables that allow for the exit of the hot air that’s inside your home. When the air leaves your home, it creates negative pressure that sucks in the cool air. This creates a self-repeating ventilation system.

Unfortunately, this system isn’t enough. You need attic ventilation fans. Fortunately, they’re very energy-efficient since you can set them to only operate within a specific temperature range. Today, many of them are also solar powered so they won’t need any electricity. Make sure that you choose ones that can move at least 700cfm per 1,000 sq. ft. of attic space you have in your home. You should also have 336 square inches of open soffit ventilation so you receive 700cfm.

Their Downside

Although these fans will help keep your home cool, there’s still some controversy surrounding them. The main point of contention is that when you have good roof insulation your attic fans will be less effective. In reality, if your home is well insulated you won’t see a significant reduction in its cool load if you add fans.

Some of their other downsides include:

  • They may increase the loss of conditioned air.
  • Their suction may cause your home to lose some of the conditioned air if there isn’t enough soffit vent space available.
  • They can also cause a dangerous backdraft that may lead to combustion problems with your air conditioner.

Determining Your Home’s Need

It may sound like these fans aren’t worth the hassle or that they’ll cause more problems than they’ll solve. However, there are some circumstances in which attic fans are useful. These include:

  • When your roof insulation is less than R-19
  • You have a thoroughly air sealed attic floor
  • There’s lots of eave soffit ventilation space
  • Your attic has HVAC equipment that’s well-insulated and sealed

When you’re ready to discuss things like your home’s roof insulation and whether attic fans will benefit it, you should consult with the professionals as Done Rite Insulation. They have many years of experience on their side that they look forward to putting to work for you so call them today.