How to Insulate Between Drywall and Brick
LESLIE: Alright. Now we’ve got William in Florida on the line who’s got an insulation question. What can we do for you today?
WILLIAM: Yes, I have a brick home that was built back in the 70s.
WILLIAM: There’s no insulation between the drywall and the brick.
WILLIAM: I was wondering, what would be the best way to do – would be to blow insulation in there, like cellulose or fiberglass? Or can I do foam or – without having to rip drywall off? I’m trying to find the easiest way to do that.
TOM: So the brick wall forms both the interior and the exterior structural surface? There’s no studded wall in the …?
WILLIAM: No, just the exterior. The interior’s drywall.
LESLIE: Right. Are there studs between the drywall and the brick?
TOM: If there is studded wall between the drywall and the brick, then that studded wall would be filled with fiberglass insulation in the typical way. If you can’t access it, then you can blow in fiberglass or you could consider blowing in cellulose.
That said, William, the most cost-effective place in your house to add any amount of insulation, even if you had no insulation in the exterior walls, is the attic. Because that is the main source of energy loss, both in the winter and in the summer. And so I would start up there and make sure that I have the right amount of insulation which, in your area, is going to probably be in the 15- to 20-inch range.
You can learn more at EnergyStar.gov. They have a calculator there that will, based on zip code, tell you how much you need. I would start there and make sure I have that adequately insulated. And if you’ve got some time, energy and money left after that part of the project, then you can go ahead and think about adding the wall insulation.
But the biggest energy savings will be to add to the attic first. Does that make sense?
WILLIAM: Yeah, it does. What would be the best product for the walls: the cellulose or the fiberglass? Or does it matter?
TOM: Either. I think either is fine, as long as it’s blown in. You may find that it’s a little bit easier to handle one or the other or one or the other might be more available in your area. But you would have – you’d pretty much have to use a blown-in at this point, because you’re not going to take your drywall down on the inside of your house.
WILLIAM: OK. Alright. Well, thank you. Appreciate it.
TOM: You’re welcome, William. Good luck with that project. Thanks so much for calling us at 888-MONEY-PIT.