Does anyone have any suggestions or comments about using a
self-levelling compound under a hardwood floor? The floor in question
uses exterior grade plywood over floor joists but the floor is slightly
uneven from one end to the other. I would like to level the floor by
pouring some form of self-levelling compound on top of the exterior
grade plywood and then installing hardwood over top of the
self-levelling compound. I am worried that the self-levelling compound
may crack when the hardwood floor is nailed down? Any comments or
suggestions you can offer would be greatly appreciated.

Thanks,
Kris

wrote:
Does anyone have any suggestions or comments about using a
self-levelling compound under a hardwood floor? The floor in question
uses exterior grade plywood over floor joists but the floor is
slightly uneven from one end to the other. I would like to level the
floor by pouring some form of self-levelling compound on top of the
exterior grade plywood and then installing hardwood over top of the
self-levelling compound. I am worried that the self-levelling compound
may crack when the hardwood floor is nailed down? Any comments or
suggestions you can offer would be greatly appreciated.

Thanks,
Kris

Why is the floor uneven. Maybe you should address the cause of the
problem rather than the symptom.


--
Joseph Meehan

Dia duit

wrote:
Does anyone have any suggestions or comments about using a
self-levelling compound under a hardwood floor? The floor in question
uses exterior grade plywood over floor joists but the floor is slightly
uneven from one end to the other. I would like to level the floor by
pouring some form of self-levelling compound on top of the exterior
grade plywood and then installing hardwood over top of the
self-levelling compound. I am worried that the self-levelling compound
may crack when the hardwood floor is nailed down? Any comments or
suggestions you can offer would be greatly appreciated.

Thanks,
Kris

i'm not sure what you are trying to accomplish---if is is "slightly
uneven", then i wonder why you would worry about it. i've always been a
little skeptical of "self leveling compound". i think some people
picture standing in the middle of the room and pouring goop out of a
bucket that will just flow to perfectly level. it's not that easy.
one of the beauties of hardwood is that it has great strength and can
span over irregularities in the subfloor...just use plenty of
fasteners. having said all that, i think you could install hardwood
over it provided that your staples get plenty of bite into the plywood.
i would also make sure it is as dry as possible---you wouldn't to
introduce moisture into the hardwood.

wrote:
Does anyone have any suggestions or comments about using a
self-levelling compound under a hardwood floor? The floor in question
uses exterior grade plywood over floor joists but the floor is slightly
uneven from one end to the other. I would like to level the floor by
pouring some form of self-levelling compound on top of the exterior
grade plywood and then installing hardwood over top of the
self-levelling compound. I am worried that the self-levelling compound
may crack when the hardwood floor is nailed down? Any comments or
suggestions you can offer would be greatly appreciated.

Thanks,
Kris

I installed hardwood last year and needed to use leveling compound in
certain sections of floor where there were large irregularities (due to
old leveling compound that had been used before the installation of the
existing tile floor) I removed as much of the old compound as was
possible, and poured new down, smoothed it and let it dry and installed
the floor. The only time I had any problems was when a staple was mis
hit and didn't go in far enough requiring me to remove the staple. At
that point the compound would tend to chip slightly, (which I would
clean out with a small handvac) but I never saw any major cracks. The
staples did require a slight but more oomph to get them all the way
through and I tended to end up with mis hits more often above the
compound than anywhere else. But overall it worked out very well.

HOWEVER, you say your floor is only slightly uneven from one side to
the other. How many inches per foot does it slope? I would say the
same thing as other posters - why bother? I only used the stuff in an
area about 2' X 3' to deal with floor dips of up to two inches per
foot. If you want to do it on an entire room, you're creating a big
hassle for yourself. On a small scale it's easy to work with. On a
large one it would be a huge pain in the butt. Almost to the point
that I'd say pull the old sub floor up and lay a new one if the
"slight" slope bothers you.

Doug

Thank you all very much for your responses. The floor slopes about 1"
over six feet so, although not dramatic, I do find it noticeable enough
to want to address the problem.

I had considered taking up the subfloor to correct the level but I was
hoping that there would be an easier solution. In some of the research
that I've done since making my initial post, I've read that
self-levelling compound will have a tendency to crumble when used under
hardwood flooring. Two solutions that were offered was a) shimming and
b) using a polymer based self-levelling compound. Shimming seems like
it would be more finicky than a self-levelling compound. Also, the one
thing that was missing from all of the sources that I read was any
mention of a specific brand/name for a polymer based compound. Does
anyone out there know of one?

Thanks again.