No one has every heard of/done this with sand?

Kimberly

For concrete pavers outside, sure. But for in the house? No way that I could imagine.

Maybe if you described the subfloor with more detail, you might get some responses. Plywood? boards? loose? squeaks? bumpy? And how far from "level" is it? etc. etc. Alternately, google it. Good luck.

Sorry, I read a lot about how to make my subfloors flat when I was installing laminate, and I never heard anything about sand. Maybe you can seek out the HD guy who mentioned it and ask him where he heard about it?

I ultimately made my wood subfloors flat by sliding a long level along the floor in both directions looking for high and low spots, then chiseling off the very high spots (such as along seams) with a wood chisel and mallet and then sanding smooth with a power sander, then I filled in the low spots with that ugly red construction paper that comes on a big roll. The red paper was annoying to work with, but it did a good job boosting up the low spots with graduating layers. I then lay a thick 6 mil cork down before my laminate planks, and my floor feels very solid and nice and doesn't squeak or creak or pop (yet!).

It would have been nice, though, to just sprinkle sand in the low spots and smoothe it out like icing on a cake! But I wonder if the sand would shift under the hardwood over time and wear down spots on the subfloor?

It was probably the plumbing guy giving flooring advice. That's a risk you take when you get big box "experts". You never know if they were pulling carts off the lot last week and now they'be been stuck in flooring BSing customers.

It's not unheard of... years ago a few manufactures had sand listed in their instructions. Not the best way to do it and you needed use use a very dry, screened silica sand. Much better ways to do this than using sand.

Ah...well, it sounded too good (too easy) to work well! The floor does have some issues (one particular spot is a little 'uphill' over the floor joist. We are planning on sanding the floor down, and pulling up the flooring to plane the joist if necessary. I also have the 30# felt to build up low spots. I have not gone over it with a level yet (have to pull up the carpet first). I'm hoping it's not as bad as I fear. I know the subfloor is OSB with some squeaks that will need to be fixed.

I am installing maple hardwood, utility grade, btw.

Is the felt the best option? I have heard of using plywood cut thin to build up the floor, but we are limited in the tools we have and I'm not sure we could cut up the plywood!

Thanks for the input!

Kimberly

Sand was sometimes used underneath floating floors, never under a fastened down floor.

The OSB subfloor needs to be 3/4" thick, 5/8" OSB won't cut it without adding on a layer of plywood underlayment.

It was in the Kahrs original, floating wood flooring instructions, to use sand as a low spot filler, under the underlyment. Consumers didn't like that method, although cheap and very effective under a floating floor. Self leveling properties and all.

Just saw DYI show in which they used the sand as a leveler as they did not want to attempt to remove old tiles which probably had asbestos. They used the sand to give a level base, then covered with self leveling cement, and then applied an underlay and then the floating laminate.

i was intrigued as I have a 100 year old cellar floor which is broken in places and am looking at level variances which approach four inches, and that would require either removing the old concrete to do a pour of regular concrete or one heck of lot of the rather expensive self leveling product.
I am still looking for my "solution" hope this helps with yours.

I use sand all the time to level floors. Playground type. preferably you cement board over the top but if your cheap floating floor wrap is fine..<<<I also sand floors for couture , then score the back of cement board so it flexes.