Gap between door and house

Old 08-01-20, 07:57 AM
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Gap between door and house

Hi all, the house I just purchased has a pilot house to access the roof deck. The prehung door installed by the previous owner looks proper and sealed on the top and sides, but the bottom is a mess. There is a staggered gap ranging from 1/4" through about an inch underneath it, between the threshold and the house. There is also what looks to be foam escaping

down here. This gap appears too large to caulk/seal normally so I am wondering if anyone had ideas how I could seal this to be watertight.

Old 08-01-20, 08:22 AM
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Welcome to the forums Tim!
It looks like they used spray foam to fill the gap under the threshold. It's common for it to expand and the unsupported portion to fall out. I'd probably add a strip of PT under the threshold .... but I'm a painter not a carpenter. Better advice will likely follow.
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Old 08-01-20, 08:50 AM
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If this door was hung correctly there should have been at least flashing as a minimum under the door, up the sides and also covering up that exposed sub-flooring, better still there would have been a sill pan. That threshold should have been sticking out beyond that concrete by about 1", so a piece of 1 X 6 PVC lumber could have been slid into the track in the under side of the aluminum extrusion so the bottom of the threshold is supported and it would cover that area under the door.
The door bottom of the door should have been set into a bed of silicon on top of the flashing.
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Old 08-01-20, 10:53 AM
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What I would do at this point is use a butyl flashing tape, and bend a lip on it so as to stick part of it to the bottom of the aluminum sill, and let the rest drape down over the gap and onto the concrete. Then as Joecaption mentioned, fasten a 1x4 or 1x6 apron under the door. Typically it should be just as long as the door is wide, if measured from the outside trim on the left to the outside of the trim on the right. Then since its stucco or mortar, you would need to use concrete anchors to fasten the apron to the house.
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Old 08-01-20, 01:45 PM
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Thanks for the replies everyone! I appreciate it.

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