After removing carpeting in the family room to replace with hardwood
flooring, the OSB has sagging between the joists. The sagging is
around 1/4" to 3/8" worst case. The hardwood installer said he
can't warranty the install because of the floor not being level.

Leveling compound specifies not to use on OSB. Can the OSB
be sealed to use leveling compound?

Is there some other alternative? Replacing the OSB with
plywood would be a major effort as the OSB is screwed
and glued to the joists.

Appreciate your advice,

Otoe

That is one of 2 reasons why I would never buy a house with OSB floors. The
other is.... pour some water on it and watch it grow.


"Otoe" wrote in message
...
After removing carpeting in the family room to replace with hardwood
flooring, the OSB has sagging between the joists. The sagging is
around 1/4" to 3/8" worst case. The hardwood installer said he
can't warranty the install because of the floor not being level.

Leveling compound specifies not to use on OSB. Can the OSB
be sealed to use leveling compound?

Is there some other alternative? Replacing the OSB with
plywood would be a major effort as the OSB is screwed
and glued to the joists.

Appreciate your advice,

Otoe

"Otoe" wrote in message
...
After removing carpeting in the family room to replace with hardwood
flooring, the OSB has sagging between the joists. The sagging is
around 1/4" to 3/8" worst case. The hardwood installer said he
can't warranty the install because of the floor not being level.

Leveling compound specifies not to use on OSB. Can the OSB
be sealed to use leveling compound?

Is there some other alternative? Replacing the OSB with
plywood would be a major effort as the OSB is screwed
and glued to the joists.

Appreciate your advice,

Otoe

Is the ceiling below open? If so, I'd put cross bracing in place between
joists. First jack the osb back in place, nail in the cross support. I'd
also consider an overlay of 1/4" plywood on top.

A 1/4" sag is quite a bit.

That's almost to the point where many folks would consider tearing it up and
replacing it with "real" plywood.

If you are trying to do it on the cheap, you CAN "seal" the OSB. "Sanding
sealer" might work. Insofar as the OSB is porous, the sanding sealer would
penetrate. I have become a fan of sealers/primers that use denatured
alcohol as a solvent: they make a good base, clean up is easy, and they DO
penetrate.

Using denatured alcohol as a solvent makes it dry quickly. And then you
slap on your portland cement based leveling compound. The sealer will keep
the water away from the OSB until the compound sets and the water is gone.


"Otoe" wrote in message
...
After removing carpeting in the family room to replace with hardwood
flooring, the OSB has sagging between the joists. The sagging is
around 1/4" to 3/8" worst case. The hardwood installer said he
can't warranty the install because of the floor not being level.

Leveling compound specifies not to use on OSB. Can the OSB
be sealed to use leveling compound?

Is there some other alternative? Replacing the OSB with
plywood would be a major effort as the OSB is screwed
and glued to the joists.

Appreciate your advice,

Otoe


** Posted from http://www.teranews.com **

On Aug 20, 9:58*am, Otoe wrote:
After removing carpeting in the family room to replace with hardwood
flooring, the OSB has sagging between the joists. *The sagging is
around 1/4" to 3/8" worst case. *The hardwood installer said he
can't warranty the install because of the floor not being level.

Leveling compound specifies not to use on OSB. *Can the OSB
be sealed to use leveling compound?

Sure can. Just slop on a gallon of cheap poly varnish (will cover a
25' square room).*
That will give you better looking sagging floors.

Is there some other alternative? *Replacing the OSB with
plywood would be a major effort as the OSB is screwed
and glued to the joists.

Congratulations, You knew all along what the right way to do it is.
Leveling compounds can be more of a nightmare than people realize
except in relatively small areas. Unless you are absolutely sure that
the floor is perfectly level wall to wall except for the sags, then
rip rip out the OSB and get flooring grade plywood down. When the OSB
is gone, an angle grinder will take care of stubborn screw remains and
adhesive and let you true all the joists so that your new floor will
lay beautifully flat. A further advantage is not having to trim door
bottoms and dealing with other mismatched levels from the surface
build up. HTH

Joe