Tub Flange and level tiling

DIY Girl · 09-13-2011, 07:57 PM

My tub was installed by the plumber with nails holding it in place. The dry waller put in the cement backer board (CBB) and appears to have appropriately placed it just above the flange for sealing etc. except on one side. At the foot side of the tub, the tub flange sticks out approximately 1/4" past the CBB because the wall is quite obviously not straight. The area is supposed to be tiled, and tile is NOT forgiving in less than level, smooth situations and I cannot figure out how the tile will be able to lay flat and be level with the rest of the wall.
Also, I have been reading that the gaps in the CBB are supposed to be sealed with mesh tape/ thin set, but how do you get this smooth and level as well, as mortar is not like dry wall mud and cannot be sanded to perfection...right? What can I do?

So my q's are:
1. How do I level the difference between the tub flange and the CBB so my tile will be flat against the wall?

2. How do I seal the joints in the CBB to smooth and level using mesh tape and thin set?
Thanks everyone!

Ron6519 · 09-14-2011, 08:50 AM

If the tub flange is close to the wall, you can carve out the back of the wallboard so the flange is tucked into the cutout and the wall plane is the same.
I don't like the wall material above the flange, I think it's a stupid application. I shim the wall to the flange thickness and overlap the board on the flange, keeping it off the tub bottom by 1/2". This way, the gap is covered and water can't get behind the wall.

**oh'mike** · 09-14-2011, 08:58 AM

Post a picture---sounds like the framing is to large for the tub.

Some wall straightening with extra 2x4s may be needed.