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Need to replace bathroom floor from joist up

Any sugestions for the correct way to replace my bathroom floor ie sub-flooring want to get it right unlike the way it was done before. Self stick tile's are what were there sub floor has water damage.

Timothy Miller
Re: Need to replace bathroom floor from joist up

Howdy, you need to first determine if the sub floor is in need of replacement or if a floor leveler or a thin under layment added to it. If you have to remove the sub floor it is likely glued and screwed down to the joists. You simply remove the screws and pull up the floor and reinstall new sub floor. The extra is first determining which way the floor joists run and the items like toilets, vanities, and tubs/ showers do you need to remove and reset or cut out around them depending on the extent of damages to the sub floor. Then you simply reinstall the sub floor with 5/8"? tongue and grove sub floor with adhesive and screws and then prep for what type of flooring you want to then install. No problem.... Or get a couple of bids....

Re: Need to replace bathroom floor from joist up

I agree with mr miller above but believe 3/4" is more the norm.

Re: Need to replace bathroom floor from joist up

We just had to replace some of my subfloor in a remodel. We had 1"x10"s on a 45 deg throughout the house. That made it fun. So we had to trim out the ones that were rotted and then fit in new. We used a 10mil plastic sheet for moisture protection. We then placed 3/4" plywood. We used a layer of thinset then 1/2" rock board. Then tile. Seems excessive, but we had to match the height of the old hardwood floors in the hallway and the old linoleum was in terrible condition.

If you are going to cut out the old subfloor, make sure you take it easy on the joists, you don't want to chip them up too bad, you still need to screw the new floor to them. So cut up to the joist, then remove the areas over the joist separately. Replace more than you think you need to, and always end the pieces in the middle of the joists. When you lay the new materials down, overlap the edges, you don't want the edge of your subfloor to be right along the edge of the rock board and then the edge of a tile. This will weaken that joint and possibly crack your grout later, so overlap as much as possible. Screw, screw, and then screw more, make sure that subfloor is secure, use an 8" spacing between screws max.

Just a general note, if you have any plumbing to do, it’s a good idea to do it while you have the subfloor pulled up, this way you can access everything easier and get the plumbing placed without running into a joist.

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