If you have a large gap at the bottom of your door that may be helping the door to stay plumb.
Gap under wooden front door.
Shim it and nail it and hang the trim.
Remove the adhesive backing and stick.
The door is probably touching the side jamb at the top of the door leaving no gap at all.
A gap between the bottom of the front door and the threshold is easily fixed with a door sweep.
To fix the issue the doors need to be removed bottom of the jambs cut and reset the door.
The odds are you ll see a larger gap at the top of the door on the top edge that s above the handle or door knob.
Make marks through the pre drilled attachment holes onto the door proper.
Install a foam weatherstripping gasket around the door frame.
Place the sweep at the bottom of the door and align the sweep edge so that it blocks the door gap.
I have never seen a door set with that big of a gap unless it was to get past floors that were not level.
The standard i use is 1 2 over finish floors 3 4 is acceptable.
Door sweeps reinforce the seal between the bottom of the door and the door jamb meaning you get extra protection from dirt bugs moisture and wind.
Reset the door so that it is level and plumb.
Pilot hole the marks.
New upgrade huge gap door draft stopper 3 2 5 w widened door sweep seal gap up to 1 4 5 for interior exterior doors keeping draft noise dust and unwanted animals out 3 2 5 w x 39 l white 4 6 out of 5 stars 1 076.
Check that the stud walls on either side are plumb before you get into bigger issues.