power vents and roof vents - Contractor Talk - Professional Construction and Remodeling Forum

232323 · 03-08-2009, 03:04 PM

I have a customer that wants to install a power roof vent along with their existing standard roof vents on a new roof. I've always thought that with a power vent, you should eliminate any other roof vents, otherwise it seems like your going to be just drawing air from the other roof vents and not from the eaves. It may not hurt anything, but seems like a waste? I would appreciate you opinions.

Jake Stevens · 03-09-2009, 01:45 PM

We use a lot of power vents. If you mean they have gable vents already, sometimes we put the power vent over a gable vent. We never install ridge vent with a power vent. If there's other vents like in a mobile home we do take them out. Make sure if it is a moble home there's not a power vent already. With all of the power vents we do, we also make sure that it has a humidistat with the thermostat.

dennis · 03-11-2009, 08:52 PM

Power vents, like any active roof vent, will draw air from the source with the least resistance. Not the closest source.
Before you remove any vents, you should make sure that there is enough intake at the soffit to satisfy the power vents draw. Otherwise air will be drawn from the house interior.

Jake Stevens · 03-12-2009, 06:47 AM

Quote:

Originally Posted by dennis

Power vents, like any active roof vent, will draw air from the source with the least resistance. Not the closest source.
Before you remove any vents, you should make sure that there is enough intake at the soffit to satisfy the power vents draw. Otherwise air will be drawn from the house interior.

The only reason we install power vents is because there's no eves on the house to vent from.

Lefty H · 03-19-2009, 05:31 PM

Hi Jake,

You can use smart vent at the eaves. The air your are drawing out needs to be replace with air from somewhere. So if you do not have intake at the eaves, the inside of the house is the next easiest place. All the electric wires and light fixtures and heat and air ducts will funnel air out of the house to the exhaust fan.