Insulate under interior door?
#1
11-17-20, 04:50 PM
Insulate under interior door?
If you can see these this is the interior of the door and it has about an inch and a half space between the door and the sub floor. That's just a piece of wood I put in there to take up some of it.
There was a leak from the door at one time but the door was replaced and the sub floor is dry now.
Are you supposed to insulate under a door on the inside? Spray foam or something else?
There was a leak from the door at one time but the door was replaced and the sub floor is dry now.
Are you supposed to insulate under a door on the inside? Spray foam or something else?
#2
11-17-20, 06:11 PM
Group Moderator
Exterior doors usually sit right on the subfloor. They also usually have an aluminum sill and adjustable threshold. Yours doesn't?
#3
11-17-20, 06:35 PM
Yes, there's an aluminum sill. I swung the door open and took another picture.
What I'm asking about is if that space (on the inside) under the door should be insulated before we put the flooring back down.
What I'm asking about is if that space (on the inside) under the door should be insulated before we put the flooring back down.
#4
11-17-20, 06:41 PM
Group Moderator
Typically there is no space because the door sits right on the subfloor. If there is a space there, your sill will bend when it's stepped on. (If not now, eventually it will) The sill needs to be supported solidly underneath with wood. If you do insulate it, I would do it sparingly, (just to stop air) because your flooring still needs to slip under the door sill to support it. If the flooring is too thin to support the door, you would be wise to shim that space after the floor has been installed.
Doors also usually sit on a bead of sealant that stops all air from passing under the door.
Doors also usually sit on a bead of sealant that stops all air from passing under the door.
#5
11-17-20, 06:49 PM
Ok, thank you. As I mentioned there is about an inch and a half between the sub floor and the sill. I had shoved a piece of foam type "wood" under to take up some of that space. Now with the flooring out there's still close to an inch of space.
So I should lightly insulate it maybe with fiberglass insulation? Support it with some shims or whatever as this new flooring will be thinner than the old carpet was. Is that about right?
So I should lightly insulate it maybe with fiberglass insulation? Support it with some shims or whatever as this new flooring will be thinner than the old carpet was. Is that about right?
#6
11-17-20, 07:33 PM
Group Moderator
Does this gap go clear through to the outside? Or does the gap only go partway under the sill? In other words, what is the sill sitting on?
#7
11-17-20, 07:49 PM
No it doesn't go thru to the outside, the gap might be about an inch deep. As for what the sill sits on I guess it's supported by something under it.
If I hadn't put the board under the door there would be about 2 inches difference between the sub floor and the door.
If I hadn't put the board under the door there would be about 2 inches difference between the sub floor and the door.
#8
11-17-20, 08:01 PM
Group Moderator
If its only an inch deep i don't know what the point of insulating it would be. You could use expanding foam but it will expand too much and make a mess. I'd wait until your floor is installed, then measure the distance remaining and cut a shim to stick under there.
