Strange gap where extension meets house
I was checking my foundation wall for more missing mortar when I came across this weird-ass gap in the “L” where an addition that the previous owner had put in meets the original wall. I’m not seeing any house wrap or insulation or… *anything* there. I can’t even tell how far up it goes. I assume I should have someone pull off the siding and see what’s going on under there? That’s definitely beyond my newbie DIY-er skill level. I doubt that I can just close off the bottom with a foam board patch and call it a day. Anybody have any idea why the builder did that and what I can do to close it off?
And yes, that extension room has been damn cold during the two winters I’ve been here.
edit: I guess it could be a chase, but it seems weird for one to be exposed to the outside like that. And there’s already a cold air return on another interior wall in that room.
Replies
insulate and seal.
As in, thread some fiberglass batts up the chase? It just seems like there's more going on inside there.
I would put a cement board or PT bottom on it, drill a hole and fill it with foam. It is strange but I can't see it doing any harm except for the cold air.