How to Patch Drywall
LESLIE: Mike in Illinois is on the line. How can we help you today?
MIKE: I have a – the drywall through the center of my house is separating at the seams.
MIKE: And it’s straight through the center of the house, down the hallway through the center of the house. And I’m not sure if it’s due to moisture in the attic, drying out and expanding or if it’s the floor in the house moving.
TOM: Mike, how old is your house?
MIKE: I’d say 20 years old.
TOM: OK. And is this relatively new or has it been around for a while?
MIKE: It’s been there shortly after I moved in.
TOM: Oh, so it’s been there like 20 years.
TOM: Yeah, I think it’s probably shrinkage. When a house is first built, the lumber is very wet and over the first couple of heating seasons, it tends to shrink a lot and you’ll get a lot of movement.
Now, over the years, you may have tried to patch it and then you just find that it opens up again. That’s very typical.
TOM: What you want to do to patch it is you need to sand it down where it’s cracking. You need to see new drywall tape on top of that. You can use the perforated tape; it’s easier to work with, in terms of the spackle, because you don’t have to worry about air bubbles behind the paper tape. Use the perforated tape, put about three layers of spackle on there, sand in between, prime, paint; you should be good to go.
MIKE: OK. If I have bathroom vents that are venting out into the attic, would that cause it or would that cure it if I …?
TOM: No, I don’t think – well, first of all, I don’t think it’s caused that but that in and of itself is a problem. You shouldn’t be ducting bathroom exhaust fans into an attic; they should continue through the attic to the exterior.
And the reason for that – you’re in the Chicago area, correct? Pretty cold there. And if you get that insulation damp, it’s not going to be very effective.
MIKE: OK. So, with it venting in there, that’s decreasing my R-value of my insulation, too.
TOM: It is. R-value is rated at 0-percent moisture. So when you add moisture to it, it goes down dramatically. So, the more moisture in the attic, the less effective the insulation becomes.
MIKE: OK. To fix that, would it be alright to add insulation on top of that after I fix that problem?
TOM: Yeah, you can add more insulation but you have to duct from the exhaust fan out of the attic. So you can do that by going like sort of through the gable wall or up through a roof vent with a proper termination on the end of it so no water gets in there. And just get that warm, moist air out. Don’t leave it in the attic.
MIKE: OK. And I’ve done some research on the internet. I’ve got two bathroom fans. To run them into one, they said to find a wire or a vent that’ll flip one side to the other so it doesn’t backdraft into the other bathroom. I cannot find that.
TOM: Well, I don’t think you really need that because, for example, if you run it to the gable wall and you have a typical bath/duct terminating type of a hood on it, that’s got a spring on it that stays shut. So it’s only going to open when the air is blowing out.
There’s another way to do this and that is to have a remote bath fan where they actually have the motor part that’s up in the attic space and the ducts just connect to the ceiling of the bathrooms. But that’s a nice system – it’s a quiet system – but it’s much more expensive to do. You see that a lot in hotels.
MIKE: OK. Well, thank you very much.
TOM: You’re welcome, Mike. Thanks so much for calling us at 888-MONEY-PIT.