Using Spray Foam Insulation in an Attic

Learn how to use spray foam insulation in an attic. Find out how to properly ventilate an insulated attic.

LESLIE: Richard in New York is the coolest. He podcasts The Money Pit. It’s a fantastic option for listening. And you’ve got a question about attic insulation. How can we help you, Mr. Cool?

RICHARD: Hi. I live in an old home and it’s – I have a large, unfinished attic that I’m going to be finishing.

TOM: OK.

RICHARD: It has, currently, no ridge or soffit vents. I’ve heard spray foam insulation will be a good product since I don’t need to traditionally ventilate the attic. I was wondering if – what you guys think of this product and if it’s right for me.

TOM: I think it’s an excellent idea if – you know, spray foam insulation is a way to go. Probably the leading product out there is one called isonene. If you can find an installer and you’re confident it can be installed correctly and properly, I’d say go with it.

However, I also want to caution you, Richard, that installing soffit and ridge vents does not have to be an extraordinary, complex project to do. I mean to put a ridge vent in, essentially you are going to cut open the ridge of the roof that’s there and it’s something that, although it sounds complicated, is fairly common for roofers to do. They use special circular saws with nail-cutting blades; can saw out that space. And then, on the overhang – do you actually have a soffit? Do you have an overhang on this roof?

RICHARD: Yeah, it’s about a foot-and-a-half overhang. Yep.

TOM: Well, that’s perfect. On the overhang, you can simply replace the solid soffit material with a perforated one because a fully ventilated attic is smart for a lot of reasons. It keeps the insulation dry and makes it much more effective and that, of course, is going to save you money in the end run.

So, the spray foam insulation is fine. I love isonene. But if not, you could also just install ridge vents and soffit vents and be good to go from there.

RICHARD: Great. You guys gave me a lot of options. I appreciate the call and I love the show.

LESLIE: Thanks.

TOM: Thanks, Richard. Thanks so much for calling us at 888-MONEY-PIT and for syncing and go. Sync and go the Money Pit podcast 24/7 at MoneyPit.com.