View Full Version : tub frame/tile question

11-11-2009, 12:18 PM
So I have posted some framing questions before, but now I have a different one. I have framed the jetted tub, leaving enough space under the edge of lip to sheath the side and top ledge with plywood, and still leave enough space under lip for thin set and the tile. I am thinking of doing it this way so the cut edge of the tile will be underneath the edge of tub. But does it matter if i tile under the edge of tub, or should i redo the frame seen below so the tub lip rests on the frame and THEN tile up to the edge? Are there any pros or cons I should be aware of?

here are pictures




11-11-2009, 12:30 PM
You NEVER want to tile directly to dimensional lumber, and it is to be avoided tiling to plywood. You really also want some waterproofing there. You should leave enough room to install either a tile-able membrane, or 1/4" cbu, and if you use cbu, I'd use a paint-on waterproofer like RedGard from Custom Building Products on top of it. The ply should be made of C grade or better faces (i.e., no voids) and exposure 1 glue (water resistant). There will be some inevitable splashing over the lip, and you don't want things delaminating or rotting as a result.

It will look much better if you tile, then install the tub so the edges are underneath the lip. For good help on tiling, check out www.johnbridge.com.

11-11-2009, 04:53 PM
If you tile up to the edge of the tub, you will have to caulk/grout the seam. And that seam will ALWAYS crack open so that any water on the deck will leak onto the floor under the tub. Caulking to a tub sitting on top of the tile does not have that problem.

11-12-2009, 12:06 AM
Don't forget that you will be setting the tub in a bed of mortar to support it. It can't rest on the lip of the tub. Your finished deck should be about 1 1/2" higher than the actual tub heighth to allow room for the mortar on the subfloor.

11-12-2009, 05:08 AM
quote; Your finished deck should be about 1 1/2" higher than the actual tub heighth to allow room for the mortar on the subfloor.

MOST tubs have a framework that is designed to sit ON the subfloor to support the tub. They do NOT have to be raised or overly mortared to be properly installed. I have only had to put a mortar base under a couple of tubs, but usually because the deck was raised so there WAS a space under the tub's support framework.

11-12-2009, 11:31 AM
Thanks for the help/tips folks.

Now my tub is a jetted 60x32 drop in, and on the bottom are 4 thick 4x4 legs that are screwed and caulked into the bottom under the plywood that the pump and heater are all mounted to. I was told these are there to use to level the tub and they just set in the mortar bed under the tub. It just seems strange to me that the whole weight of the tub sits on those 4 legs instead of the plywood base. But I have seem other pics of tubs that have fiberglass looking legs, is this normal?