Vented Attics Versus Unventilated Attics
LESLIE: Heading up to the attic with Richard in Texas. What can we do for you?RICHARD: Yes, I’m looking at building a new home and I’ve been reading quite a bit about unventilated attics and just wondering what are the benefits; what is the drawback. Because the attic temperature is what I used to fight up in Minnesota with cold; it’s now heat in Texas.
LESLIE: Don’t you need the circulation of air through the attic to sort of help control the air throughout – you know, the conditioning throughout the rest of the space?
RICHARD: Well, they’re saying that where you like totally seal off the attic your home and your attic never gets more than a five to ten-degree temperature difference.
TOM: The answer to your question, Richard, depends on where the insulation is. Now if the insulation is above the attic, so to speak, which basically makes the attic really conditioned space as opposed to unconditioned space, which is the way it normally is done; if that, in fact, is conditioned space, then the temperature up there is going to be fairly consistent with what the interior temperature of the home is.
TOM: Now, that’s one way to do it. The other way to do it is to use a traditional vented attic. Where I see most contractors go wrong is that they don’t put enough venting in the attic. They put small vents; just soffit vents; maybe a couple of roof vents. What we have found is that if you use a continuous ridge and soffit vent that goes all the way down through the soffits on the both sides of the home and all the way down through the ridge then what you, in effect, create is a 24/7/365 venting system where the air gets sucked out of the ridge and pushed into the soffits and always keeps that attic very comfortable.
So those are two different ways to go. Which one you choose is going to depend a lot on your builder and which way they’re accustomed to working but I think that they’ll both work.
LESLIE: There’s actually a great resource online; it’s BuildingScience.com and if you go to their website and go through the resources you can find an article on roofing and roofs and there’s a full scientific study on vented and unvented attic spaces.
RICHARD: OK. Very good. Thank you.
TOM: You’re welcome, Richard. Thanks so much for calling us at 888-MONEY-PIT.