Tuesday, August 5, 2008

Attic Ventilation Lowers Utility Bills


Sure, you've maxed out your attic's recommended insulation R-value. But don't start loafing quite yet; there's still work to be done to take the load off your AC and wallet.

Categories of Attic Vents

Installing an attic vent is a simple DIY project and in most cases you can be done in a couple of hours. There are two categories of vents/fans. The first kind is passive roof venting. This includes turbine or whirlybird fans as well as ridge vents.

The second category is the active vent. These are electrical; either home-wired or solar powered. These are activated and shut off by thermostats and occasionally, humidistats. These are mounted either on the roof top or on the gables.

Installing Attic Vents

Ridge vents run the length of the roof ridge and are best installed during new construction and when doing a re-roofing job. The shingles on the vents will match the roof shingles so the look is very slick.

Turbine and power vent installation can be done at any time. It involves computing the attic CFM requirement, cutting a hole in the roof, and installing the unit. Some wiring is required on electrical powered units.

Are Solar Powered Vents Worthwhile?

Sadly, the answer at this point is no. While we would all love to adhere to green building practices, the pennies just don't add up here. Why? Solar powered units are expensive and direct-wired ones use very little juice compared to what they shave off utility bills.

Of course, if you just install a whirlybird (turbine), there is no external electricity involved. The fins on the globe spin in the wind and draw cooler air through your soffit vents and hotter air out of the attic.

Modern ones have sealed bearing races. They never need lubing and run silent, like a submarine in stealth mode.

Which ever way you decide to go, your options are wide open. Chill out.