Open the door fully and slide on the door sweep at the bottom of the door.
Large gap between door and floor.
Measure the gap between the door and the floor.
This is what i particularly suggest for the front door to keep our.
Reset the door so that it is level and plumb.
If each room has individual air returns the numbers can be smaller for personal taste.
There is an approximately 1 5 gap at the bottom of the doors.
The door gap to the floor should be 5 8 to 3 4 inch.
As we are focusing on uneven floors mostly you need to measure the size of multiple gaps your garage door has from the floor.
The foam should be the same diameter as the width of the gap.
Check that the stud walls on either side are plumb before you get into bigger issues.
This is a simple solution to your problem.
Press a closed cell foam backer rod into the gap starting at the corner.
This is the alternative to using a door sweep.
Foam backer rod is a flexible rope that compresses to fill.
This number is regardless of flooring.
Here the gap is the distance between the floor and the bottom of the door.
I think it is too big and think a 1 4 1 2 gap would accommodate any unevenness in our floors and allow us to use area rugs.
Because smaller gaps will transfer the air as efficiently as larger gaps there is no real reason the gaps need to be 3 inches.
It should be measured from the floor surface to the bottom of the door.
This allows for proper air exchange between rooms.
The contractors tried to seal it using caulk but it doesn t look so great in my opinion.
The larger the gap the more sound that seems to transfer between rooms.
Shim it and nail it and hang the trim.
Under all the door casings there is a gap between the casing and the hardwood floor.
If you have a large gap at the bottom of your door that may be helping the door to stay plumb.
My contractor just hung our fancy dancy un painted solid wood door slabs in my 100 year old house with solid hardwood floors throughout.
It is about a little less than a 1 4 of an inch.
The head casing should cover the gap created up top although you might have to touch up the paint on the gyprock.
When we remodel manufactured home we almost always replace the interior doors with new and better ones.
Pop the door and frame cut the jambs down by a half inch and re install with the jambs hard down.