Hanging New Interior Doors

[Joe Angrisani]

Time has come in my slowwww remodel to hang doors. I have a question regarding the bottom clearance of the door.

How much clearance is generally kept between the door panel itself and the subfloor? All doors in question will be over carpet, but all I have now is subfloor. We plan to use a top-grade carpet padding and "better" carpeting. Is there some kind of standard clearance amount?

[Dave Zellers]

I used to leave 1 1/8" to 1 1/4" when I did it back in the day. Carpet comes in all different thicknesses. Pads are generally 1/2".

[jared herbert]

I have hung a lot of doors in my own houses and it seems like a calculate how much clearance to allow and then after the flooring is installed I end up cutting some more off. I always look at doors in other places and have decided that a little extra clearance is not objectionable or easy to notice and nobody cares anyway. The 1 1/4 look like a lot on bare floor but Iwouldnt go with any less. Jared

[Joe Angrisani]

Thank you Collective Wisdom. I went with 1-1/4".

[Leo Graywacz]

It can depend on your heat, believe it or not. If you have forced air for heat and AC then you want to have about 3/4-1" of space under the door for the airflow to the return ducts. If you have any other type of heat then you want 1/4 to 1/2" remaining.

So you need to know what your flooring will be that is going over the subfloor. They now come in all flavors ranging from 3/8" to 3/4". With tile you may end up with more build than that in some instances.

Top grade carpet mean little. Shag, berber, ????. Most nice padding is 1/2" as was stated.

[Dave Zellers]

It can depend on your heat, believe it or not. If you have forced air for heat and AC then you want to have about 3/4-1" of space under the door for the airflow to the return ducts. If you have any other type of heat then you want 1/4 to 1/2" remaining.
That's an excellent point and I was going to point that out regarding bathroom doors and shower fans. Bathroom fans are really important for removing moisture from the bathroom after a shower but if someone closes the door and there is no gap under the door to pull air in, the fan is spinning but nothing is happening. A 3/4" gap under the door is all that is needed to allow the fan to pull in dry air and exhaust the moist air.

There is really nothing to be gained by cutting doors to tightly fit at the bottom, bedroom or bathroom.

[Leo Graywacz]

That's an excellent point and I was going to point that out regarding bathroom doors and shower fans. Bathroom fans are really important for removing moisture from the bathroom after a shower but if someone closes the door and there is no gap under the door to pull air in, the fan is spinning but nothing is happening. A 3/4" gap under the door is all that is needed to allow the fan to pull in dry air and exhaust the moist air.

There is really nothing to be gained by cutting doors to tightly fit at the bottom, bedroom or bathroom.

It looks real nice.:)