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Door threshold help

John Holmes's Avatar

Join Date: Sep 2015
Posts: 8

09-11-15, 12:48 PM   #1  
Door threshold help


I recently purchased a home that has a sagging exterior door threshold (I think it's a threshold?) when stepped on. I believe this sag caused rotting of the door trim, which is one of the first things I had replaced.

Original issue: rear entry door trim rot
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My guess is that there was originally caulking between the trim and threshold, but the caulking was compromised because the entire threshold would move when stepped on.

I had the threshold sagging repaired but I don't think the repair went far enough. The repair person used a 1x3 board (not treated) board underneath the threshold to prop it up. It helped, but there was still sagging. In the video you will see the leftover nails where I pulled


What is the right way to repair the sagging ? Two thougsh:

1.) Place some shims under the threshold ? If so, should they be treated, plastic ?

2.) Take out the sill and replace it with concrete ?

I appreciate any advice!

Thank you,

This is a picture of me pressing down on the threshold, along with what I am calling a sill and threshold
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This is a picture of the uncompressed threshold.
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A picture of the sill (under the threshold)
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Overview picture
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Overview picture 2
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XSleeper's Avatar
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Join Date: Dec 2004
Posts: 19,284

09-11-15, 02:25 PM   #2  
Plastic shims. Treated wood eats aluminum. Then place a 1x4 under the door sill (pvc is best) and fasten it to the wood under your door. This will help support the front of the sill. (A threshold is the part that is directly under the door when its closed.)

John Holmes's Avatar

Join Date: Sep 2015
Posts: 8

09-12-15, 07:01 PM   #3  
Thank you!

I appreciate the advice! Thank you!

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