i have a great room that is about 30' long and 20' wide. from the foyer, u look at the length of the room. the floor joists run with the length. the sub-floor is 3/4" ocb. the adjoining tile foor is between 7/8 and 1" above the sub-floor.

i wud like to run the wood with the length. i was thinking about putting down a 1/4" underlayment but wud rather put down a 3/8". however, the 3/8" would make the hardwood higher than the tile. i'm trying to avoid a height transition.

i'm considering either red oak or brazilian walnut. the latter is much heavier and wud add much more weight to the floor.

wud i be safe with a 1/4" underlayment plus the 3/4" ocb or do i need the 3/8"?

thanks

zman

You may get by with 3/8, but my rule is ½" minimum, to run with the joist. If you can get under the floor and add blocking, every 16 or 24 inches, then the 3/8 wouldn't be a big concern of not being enough.

r u saying that u prefer 1/2" in addition to 3/4"?

id i go that way, what wud u suggest for a transition with the tile, which is arounf 7/8" to 1"?

thanks,

zman

OK, now I'm confused!!

3/4, I read 3/8

sorry, floorman. i have 3/4" ocb now. wud 1/4" extra be ok or do i need 3/9"?

zman

Bollinger and most installers say 1 1/4" total to run with the joists.

Steve

3/4 + 1/2 = 1¼

That is what I'm trying to say.



I did read 3/8ths I see it. I was saying, it really isn't enough beef.