Is My Whole-House Fan Letting Cold Air In?
LESLIE: Now we’ve got Linda in Pennsylvania on the line with an insulation question.
LINDA: We have a two-story house built in the late 1980s. In the winter, it’s colder upstairs than downstairs and especially in the summer, it’s just really hot upstairs. We also – we have a whole-house fan and it’s – I don’t want to get rid of that. The one person that came and talked to us about insulation said we should get rid of that. I don’t know – rather the fan has blown some of the insulation over that blocks the soffit vents that we’re not getting enough circulation. So I guess I just don’t really know what to do about adding more insulation.
TOM: Alright. Well, first of all, a 1980s house probably has a minimal amount of insulation. What you really want is 15 or 20 inches of insulation.
Do you have decent space in the attic? Can you walk around up there?
TOM: OK. So how is it constructed? Is it made of trusses, where it’s hard to get around?
LINDA: Yes. And it’s not real high in the center. I mean you can get around but no, it’s not very high up there.
TOM: I would have blown-in insulation installed, because you can easily – a professional can get that where it has to go. Professionals are also good at making sure that the baffles are in place, which keeps it out of the soffits.
And then when it comes to the whole-house fan, you should have a cover for that for the wintertime, just to kind of seal it up a little bit. Perhaps cover it with some sort of an insulation blanket and then you can pull that off in the summertime. It will be a source of energy loss, so you have to kind of take that additional step. But I agree: it’s a great thing to have. But I will say it must have good exit venting, though, too.
Do you have big gable vents on the side walls of the house? Because when you turn that fan on, you don’t want to pressurize the attic. You want to make that air go out.
LINDA: No, we have the ridge vent. And when they replaced the roof a couple years ago, they did put in – they said there is a slightly larger-size ridge vent and that’s what they put in.
TOM: Alright. Well, then, that’s probably big enough to handle the exhaust venting.
So that’s what I would do. I would use blown-in insulation. Now, around the fan itself, what the installer will do is put sort of a wall around that made of sort of like a stiff cardboard, or some type of material like that, so that they can pile the insulation up higher against that opening and keep it away from the operation of the fan.
TOM: It’s done all the time, Linda, and it’ll definitely make a big difference in how comfortable you feel in that house, OK?
LINDA: Alright. Thank you very much.