Sealing OSB flooring?

[Lorne]

Bathroom floor is 5/8 OSB over 3/4 Ply Sub floor.

After the new shower is installed there will be roughly 28 Square feet of bare OSB flooring exposed.

#1
I want to put down Peel and Stick Tiles and thought of sealing it with a good coat of cut Shellac, just to make a smoother, dustless surface. A quich once over with sand paper and it gets really smooth. Does raise the grain a tad.

#2
Should I lay down a piece of Orange Rubber Membrane under the shower pan first? Or would 6 Mil Mylar do as well?

[Brenda (OH)]

Lorne,

For a bathroom floor, there is a flooring I like called Allure, it is sold at home depot.

It is vinyl planks, with a glue strip. the wood grain patterns are 6 inches by 3 ft, the tile patterned ones are 1 ft by 3 ft.

the flooring is almost water proof, since the glue strips overlap by about an inch. the subfloor does not have to be perfectly smooth. and the stuff installs very easily, it is a floating floor so no adhesive is involved.

When I am doing peel and stick, I use spray adhesive (3M 90 grade) on the subfloor and on the tile to really get those tiles stuck down.

I like the idea of sealing the floor to help give it some water resistance. don't know what would be the advantages of the membrane vs mylar. if the pan cracks, you are going to have to repair it quickly, because any water that gets under the pan is going to cause problems somewhere, whether it is on that floor, or it goes under the wall and into the a closet etc, or if it goes down and ruins the insulation and pulls off the belly wrap under the home..... (ooh, the bad memories this is bringing up lol)

Brenda (OH)

[flcruising]

You have OSB over plywood? Was this something you installed and why?

1. I believe your installation instructions for the tile should be your first resource to answer this question. At minimun, I would assume 1/4" plywood underlayment. Shellac and sanding seems like alot of work and mess just to prep the OSB. In my experience, OSB tries to delaminate when anything wet (water or oil-based) is applied to it. Shellac may be different, not sure though.

2. Any waterproofing you do under your shower is a good thing. I've never heard of using mylar as any waterproofing though. It's simply plastic. A liquid/sheet membrane, I believe, would be a much better route.

[Yanita]

I am with FLCruising...why 2 layers of subflooring in the bathroom?

Also, jmo, but completely against any peel and stick or other similar products in the bathrooms.

Any type of future water leak that may happen and you are going to have a huge mess with 2 subfloors and finished floor.

Yanita

[Lorne]

Well lets see here.
Brenda, I saw allure today and it looked perfect for what I need.

As for the flooring I stand corrected. It is 3/4" Weldboard by US Plywood. Structural OSB, which I call "Chipboard". Put down i in 1986. Clean as brand new.

If there is a major water leak everything will be toast anyway.

[Yanita]

Well proper installation would be to install 1/4 inch luan. When laying that make sure that its joint are staggered from the sub floor. Float all seam and nail/screws. Then install finished floor.

Yanita

[Greg]

Lorne, OSB WILL take some abuse from water, It takes a major long term soaking to break it down. It's not like partical board that starts falling apart 30 seconds after the first drop hits. Greg

[Jim from Canada]

I suppose you could seal the chipboard floor, or you could use a waterproof membrane (schluter makes them, designed for bathrooms, or you could put down the Allure flooring. But, IMO, not any combination of the three. The reason being, is that you will have 2, non porous surfaces together, and that equals mold. Any dampness, including that of the humidity during installation, will be traped between the surfaces and will not dry out.

Jim

[Brenda (OH)]

The allure flooring is a floating floor, and unless the osb flooring is not level where edges meet, you can install allure right on it. allure can typically handle up to 1/8 inch height differences or 1/8 inch gaps.

only time I have put a membrane down for it was when I had a room that I took up peel and stick tiles and the floor was very sticky, and I thought it might not allow the allure to float. I put 6 mil plastic down on the floor, then put the allure down.

my favorite thing about allure is still the score with a utility blade and snap it cutting feature.
I have even come up with a technique where for small cuts, I score the material, then bend it with pliers and it will pop off, which I use for making cut outs around things you find on mobile home floors, like the weird 220v outlet that is on the floor of the living room.... or the gazillion cable tv cables that come up through the floors....lol

this is vs laminate that I have to get up off my knees and walk over to the saw to trim a board. saves me $30 right there not having to sharpen the 12 inch saw blade, but I guess that it is my preference for using the compound miter saw vs a circular saw. It doesn't help that my circular saw is odd sized, and is hard to find blades for also lol.

Allure installs quickly, tends to color match from lot to lot, and since I get it at home depot, i can run and get an extra box or return unused boxes easily. I just wish it had more shine to it.

Brenda (OH)

[Lorne]

Another discovery today. The top flooring DOES say 5/8 but I found a bottom layer which is 1/4, so this explainse the 3/4.

[blbrade1]

i would have to strongly suggest not using peel and stick or allure peel n stick cause it never last long before cracking and peeling up and alluer cause it is a floating floor and u cant caulk the base trim therefore leaving a place for water to go and there will be alot of water on that floor over the years (its a bathroom) if you try to caulk the trim then the flooring will not be able to move like it is engeneered to do and buckle at the seams i wuold go with tile or vinyl there is a reason why you dont see contractors using peel n stick or alluer style floors in bathrooms