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Community and Q&A

Air leak under new glass sliders

Oopey | Posted in Energy Efficiency and Durability on

We just had new glass sliding doors installed a few months ago (there used to be a very old swinging door in that location, so the hole was enlarged and a new header was put in).

Now, I can feel a lot of cold air leaking in from the bottom. There is no moulding between the laminate floor and the door yet – I am in the process of putting quarter round moulding there, but there is a kick-lock so its taking me a long time to get the cut-outs right to fit around the kick lock.

My plan is to glue a strip of something very thin (felt?) under the moulding and then glue (liquid nails?) the quarter round moulding to the very bottom part of the door (i.e., not to the floor). I can’t nail it to the bottom of the door as its metal, not wood. Any thoughts on if this will stop the air leak? Any other things I can try?

(When the door was installed, I had the installers put spray foam between the door frame and the wall instead of using the pink fiberglass stuff.)

Thanks for any help.

EDIT – there is an uninsulated crawlspace below, about 3′ tall with a cement floor; no basement. We are NYC area.

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  1. GBA Editor
    Martin Holladay | | #1

    Assuming that the crack you want to seal is between the finish flooring and the track that holds the sliders, I think that all you need is clear silicone caulk, neatly installed.

    If the crack you want to seal is between the door and the track, you need some type of weatherstripping.

    And by the way, I wouldn't hire the contractors who installed the door for any future jobs. They should have installed caulk under the sill when they installed the door.

  2. Oopey | | #2

    Thanks for the info. There doesn't seem to be any air leaking from between the door and track; it seems to be from between the track and the laminate flooring. I am just not really sure if the air leak is from outside or from the crawlspace (although maybe it doesn't much matter).

    I guess I will try the clear silicone caulk and then put the quarter round moulding over it...would you recommend the felt (or whatever) at the bottom of the moulding?

    Thanks again.

  3. GBA Editor
    Martin Holladay | | #3

    Assuming that you have caulked the crack, there is no need for the quarter-round molding. At that point, whether or not to install molding is an aesthetic decision.

    I wouldn't install it -- it interferes with cleaning the floor and collects dust. But it's your house -- so if you like the look of quarter-round molding, go ahead and install it, with or without the felt.

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