I am collecting items for a hardwood floor install.
About how many square feet coverage does one get from 1 roll of roofing felt? Assuming 3" overlap.

Mr Bill5

400 sq.ft.

It says 433 sq.ft on the rolls I buy.

Thank-you.
I appreciate it.

Mr Bill

MrBill,

I didn't think you would want to overlap your felt paper as hardwood flooring underlap.

perryrip

Depends on the wood flooring! On a 3/4" solid, one can overlap the #15 asphalt felt. On thinner engineered, it is better to butt the felt together or use a different flooring paper.

Gary,

Thanks for the insight. I learn something everyday I'm on this forum.

perryrip

I have Mercier 9/16" thick solid hardwood flooring.
Butted paper or overlapped?

Mr Bill5

Ground floor, or second floor?

Ground floor, I'd overlap. Also running the paper the opposite of the flooring

Second floor, I'd butt it

Perry, what is the reason for running the paper opposite of the direction of the flooring? Never heard that before, and seems like a real pain on larger rooms.

I gotta hear this one.

If the seam top lands right across the floor, in the right spot, it caused one of my jobs to have a gap down that row. I I color filled it as I went, so no one would see it.

The board actually rocked across the seam edge. Just the edge being a tad higher, had results I had not anticipated.

It only happened to me once

My project is a ground level floor over a cellar. The cellar ceiling is has foil covered fiberglass insulation between the studs.

Mr Bill

We use 30 lb felt here in the super humid south and lay the felt in the opposite direction of the flooring too. When a board (row) lands just short of the lap when using the 30 lb felt laid in the same direction of the flooring, the next board is the thickness of the felt higher than the nailed down row making it more difficult to pull up the higher board.

Buddy