What is the most appropriate way to adjust for an uneven threshold on an exterior door?
In the image below you can see the gap that exists on one side of the door.
We have considered taking up the metal threshold and using self-leveling concrete to even out the corner, and threshold. Is there a more appropriate way to handle this gap?
Like the previous poster, attaching a new door sweep is one possibility. Another is to replace the threshold with an adjustable one. It can be raised or lowered on each side according to the need. Caulking is absolutely crucial whichever you do. Good luck!
One way to address this problem is to acquire a lower door threshold seal unit that slides onto the bottom of the door and is adjustable by sliding up and down to the threshold. They are then fixed into place using screws through the side flanges into the lower rail of the door.
Here is a picture of what the product looks like. They are sized to the specific thickness of the door.
You would remove any existing lower door seal before installing the new seal. In some cases it may be necessary to trim the door some if the lower height requirement of the new piece is more than the current gap under the door.
You should be able to find these at most big box home stores. I saw mention of the orange one online.
Here are two more solutions I've come across. I'm inclined toward the first.
use peel and stick roofing underlay to build up to an even threshold: https://www.youtube.com/watch?v=p36A6s4WYic
trim the rubber piece of a door sweep: https://homeguides.sfgate.com/seal-door-uneven-floor-41550.html
