I purchased Bruce 3/4" thick solid maple tongue and groove flooring to install in my 2nd story bedroom. I thought the subfloor was plywood when I purchased it, however now that I pulled up the carpet I discovered that it is plywood that has been coated with some sort of cement or soft concrete. I live in Southern California and there is generally not a lot of humidity here (or rain lately either!).

I was going to nail it down but I am unsure if that will be possible because of the cement coating over the plywood. I then thought that I would try using a vapor barrier and a layer of felt and then glue the maple planks together as a floating floor, but I have since read that solid maple planks should not be glued together as a floating floor because of it's expansive properties.

Is there any way that I can install my solid maple 3/4" thick 2-1/4" wide tongue and groove plank flooring over my existing subfloor? I bought the flooring more than 90 days ago so I can no longer return it. Thank you.

It really sounds like you're out of luck, unless you installed another layer of plywood over it and use 1 1/2" staples or nails. Naturally that would raise the height substantially...but...one never knows. Nice sloping reducer at the doorway? That must lead to a hall? What's there now? Carpet?

To even consider that to work, one has to know if the concrete stuff is going to crumble when fastened if considering another layer of ply.

Have any pics?

Maybe you'd be better off selling what you have on Craigslist and go with a floating floor.

Thank you for the response Ken. I think "He ran out of luck" will be the epitaph on my tombstone.

I am considering trying to sell it on CL (or storing it for a future project at another home if I move soon) and buying click lock flooring. The click lock is crappy floor though, I really like solid hardwood. I hand nailed my entire last home with solid oak and that floor will last forever. It would be too difficult and time consuming to raise the subfloor or remove and replace the old subfloor, and it would not look too good as it will be quite a bit above my sliding door.

I took a pic of the subfloor. I have no idea what the heck it is though, I am originally from back east and I never saw this before and I was not expecting it. It looks like concrete to me, and I know there is plywood underneath it as I saw it from below. I beleive someone told me the coating was added later, possibly because of noise issues between condo units.

http://i1287.photobucket.com/albums/a634/Hypermotard/cementsubfloor_zps9de91fa7.jpg

I do have quite a bit extra (40%) of the solid maple hardwood, and the place where I would use the extra can be nailed down to a plywood subfloor. I was hoping that I could remove all the "bowed" boards and just glue the straight ones together and float that over a vapor barrier over the cement coated floor. Then I could nail down the not-as-flat boards in the other room where there is a plywood subfloor. Unfortunately it seems hardwood maple is one of the worst candidates for a floating floor

If the concrete is soft it is probably Gyp-Crete not good for anything except floating. Look at Mirage for their locking floors or their regular engineered. I love installing the lock but prefer the wear layer of the engineered.

Also they might take back the solid if you buy something else from them. Otherwise I wouldn't give them any more of your business. Natural maple should be a stock item.

Yup, gypcrete. Usually one to one and a half inches thick, used in condos and apartments alot.

You can glue it with Bostiks Best or Ultra Step.

let the sticky stuff and gravity do its thing.

you will need straps to pull the courses tight.

a power jack to close at the walls is useful as well.

if you are inexperienced then this may be a very difficult install for you.
A quality mill/product is especially important

you can also look into Elastilon underlayment.

That is interesting, the adhesive moves with the wood I really want to try to put the flooring that I already have down. It was special ordered because Home Depot does not stock natural maple floor out here so I won't be able to return it.

If you don't mind me asking a few questions, how much would I need to lay 200 sf? That Bostiks is kind of pricey, but if it will work I will splurge Also, do you think it would be a good idea to first glue 4 rows of flooring together with t&G glue, and then adhesive them down after they are one solid piece (now a 9" wide plank - 4 rows of 2-1/4") to the subfloor? I can make brackets and use ratchet straps to pull the flooring together, and then lay a few hundred lbs of weight plates on top of the 9" x 12' plank to glue it to the floor. When I get to the end I would probably just lay aluminum stock along the wall and hammer some wooden wedges in to squeeze the last row tight.

I would like to try this on this one room if it is possible. I really like solid flooring, everything else is crap in my mind.

Thank you for your help James, and everyone else too!

I looked into the elastilon, that looks easy as pie I may try that as it looks like to won't be too messy and it should go very quickly. $400 for 200 sf is quite pricey though. Thank you again.

you will need 2 pails.

you wont get very far glue coverage. it requires 1/2" trowel spread.

so the costs will wash out.

decide which product makes the most sense for your skill set.

Thanks James, I am going to go with the elastilon as it will save me some time and it looks super easy and not messy. It will probably cost an extra $100-150 over the trowel method but the time savings will be worth it.

Btw, I am originally from Passaic County NJ too

Glad to help Cecil..come back with a pic and any other comments of your installation..good bad and certainly ugly..

best of luck.

If you do glue down the maple flooring , it's probably best to get your first row glued down, let it dry for a day and then continue the install.That way, you can strap against it or pull against it without it moving.

Thanks, I will post how the elastilon works out after I order everything I need to do it and finally get to do it in a couple of weeks. Elastilon states not to strap it - just push the boards tight together (rubber mallet ok) and then pull the foil layer off while pushing down on the new board. I will put 50 lbs of weight on it every couple of feet on cardboard and just slide the weight over the new boards as I lay them. The deciding factor was that the elastilon supposedly adds some soundproofing to the floor, and I am in a condo above another unit.

Thanks Paul, I won't be gluing this time around but if I do in the future I will certainly do as you have suggested.

I started the install with elastilon today. The instructions should be thrown out... I glued 2 rows of 2.25" wide maple planks together of the longest and straightest boards I had, then I shimmed the wall so it had the gap required and it was perfectly straight. Then I removed the elastilon coating for the first two board widths and slid the first boards down the wall and into place.

When installing the next rows it is impossible to get the boards tight - and using a mallet or painters tape like they suggest is a joke. I tried ratcheting from the first board but the elastilon and boards move because it is not attached to the subfloor (the elastilon floats on the subfloor) so that was out. I can see why they say not to ratchet the boards together.

So what I did was I put down a row and got it as tight as I could by pushing, then a 2nd row, then a 3rd row, then a 4th row. Then I put 2x4's against the opposite wall perpendicular to the flooring and laid them across the room every 30" or so. Then I put 12" wood spreader clamps on them and pushed from the far wall against the 4 rows I just put down and squeezed them into the wall with the shims. The 4 rows of boards tightened right up! Then I put 50 lbs of weights over the 4 rows opposite each clamp and then I walked on the boards for a couple minutes.

Then I lay out the next 4 rows of boards and wait until 30 minutes has passed, and then I remove the clamps and repeat the procedure. It is taking more time this way but it is coming out pretty nicely and the floor feels very nice under foot, and I suspect the elastilon will have better soundproof qualities over gluing. I only did 1/3 of the room so far, but I will post an update after I finish.

Although it is taking time it is very nice to be able to work in my shorts, no shirt and bare feet - it was 100 degrees here today! It is a very clean way to lay flooring and the elastilon is easy on the knees while working.