Insulating Your Crawlspace

 

TIM: Well, I have a basement crawlspace and what’s the best way to insulate it? Right now there’s just nothing there.

 

TOM: So it’s a crawlspace or a basement?

 

TIM: It’s actually a – on one side, I have a full walk-in basement.

 

TOM: OK.

 

TIM: And on the other side, there’s actually a crawlspace; looks like a half-finished basement. But I can see …

 

TOM: OK.

 

TIM: Looking into the other side, it’s like a crawlspace.

 

TOM: Alright. In the crawlspace area, you should insulate the floor from below. So if you have like 2×8 floor joists, you should put eight-inch-thick batts of fiberglass insulation in there and they can be held up with insulation supports which look like kind of small wires that sort of get springy in between the floor joists.

 

TIM: Right, I’ve seen those. OK.

 

TOM: Right. That’s the best way to insulate that. As far as the basement …

 

TIM: How about the pipes? There are some pipes down there.

 

TOM: Not necessary. Generally not necessary to insulate the pipes.

 

TIM: (inaudible at 0:21:47.7)?

 

TOM: Yeah, mm-hmm. But insulating the floor is going to make you a lot more comfortable upstairs.

 

TIM: I have oil heat; oil – like steam heat, I guess.

 

TOM: OK. Right.

 

TIM: Is that going to be OK?

 

TOM: Sure, I don’t see why not. Now, as far as the basement, the only place you really need to insulate an unfinished basement is the box joist, which is above the wall all the way around. If you decide to put walls in, like finished walls, and you’re going to frame them out, then you could put insulation in the framed walls; but, other than that, you should just insulate the box joist right above the foundation.

 

TIM: Now, I’ve seen a place where they’ve actually taken like plastic and they staple-gunned in between the joists after they put the insulation up. Is that recommended or no?

 

TOM: No, I would do not do that because, if you’re talking about the crawlspace, the vapor barrier goes between the insulation and the living space.

 

TIM: OK.

 

TOM: Which means it would be above the insulation; against the underside of the floor, not below it.

 

TIM: Alright.

 

TOM: Because if you put it below it, you’re going to trap moisture in that space and …

 

LESLIE: And you’re going to reduce the r value.

 

TOM: Exactly.

 

TIM: Got you. OK. Alright, I think that’ll do it for me. That’s all there is to it. There’s nothing – besides that, there’s no other tricks we’ve got to do?

 

TOM: (overlapping voices) Nope. Nope, it’s a good project and one you can get done in a weekend.

 

TIM: Sounds great. Thank you so much.

 

TOM: You’re very welcome. Thanks so much for calling us at 1-888-MONEY-PIT.