Replacement Window Installation: Gap Too Big?
LESLIE: Wanda in Tennessee, you’ve got The Money Pit. How can we help you today?
WANDA: My home has replacement windows in it already and we were changing them out with some new replacement windows. But when they began the installation, I noticed, when I was standing outside watching them, the first window had a gap of 1 inch between the brick and the window itself, all the way around it. And my thought was, “That seems like an awfully big gap to stuff insulation in and then put a trim on.”
So after they did the second window, I said, “You just need to stop. I think that looks wrong.” And they kind of looked at me and I thought to myself, “I have to call The Money Pit and find out: are they doing it correctly or am I wrong?”
TOM: Wanda, I mean it sounds like a big gap. Typically, the space around a window is going to be more like a ¼- to a ½-inch and then it’s shimmed, because this allows the house to sort of move around the window, so to speak. And it is filled with insulation. But is it tight on the inside frame and the gap’s only on the outside? Or is it open that much all the way around?
WANDA: No, on the inside it was probably a quarter to a half and they just filled that with the caulking. And then when I went outside and I went, “Oh, my gosh.”
TOM: OK. But you have to remember this: the window can only be as wide as the hole and the hole is inside to inside. So it sounds like it was measured correctly on the inside.
Now, when it comes through the wall, there probably, in the old window design, was a brick mold or a trim that went around the outside of that window that was wider. And very often, with the old wood windows, there is a brick mold. That’s what actually – when I say brick mold, that’s what it’s called; it’s called brick mold and it’s a type of wood trim that’s about 2¼ to 2½ inches wide. And that may have extended to the edge of that brick.
Now, you don’t fill this up, though, with insulation; you retrim the window to cover that gap. And what has to happen here is they have to tell you how they’re going to trim out the window so it looks right on the outside.
WANDA: OK. But the gap – the space that’s in between the drywall and the brick, the outside where they put the trim – will they put – should they put fiberglass insulation or should they – I know some of them were putting – squeezing the foam in there.
TOM: No, not when it gets past the exterior wall. The wall cavity itself, yes, that all should be sealed in. Typically, the insulation doesn’t go all the way out but it wouldn’t hurt it. The key here is that we want to make sure that it’s – that the seal between the window trim and the brick is good so you don’t get water behind that.
WANDA: OK. Alright. I appreciate it. Thanks.
TOM: You’re welcome, Wanda. Thanks so much for calling us at 888-MONEY-PIT.