I'm in the process of installing a 36in sq shower in my basement. Please let me know if this process is correct:

1) frame out surround, 2x4s, spaced 36in for base to fit, drain and plumbing run
2) put shower base (w/ drain installed) down onto concrete (do I need to put some mortar or anything down below this?)
3) put cement board up to height of where tiling will end, then butt together w/ greenboard for area above tiling, tape seams (is this right, I'm not sure where the cement board should end, will regular self adhesive fiberglass tape work? Also, how high should tiling go?)
4) install tiling up wall
5) seal grout
6) caulk between bottom of tile and shower base

done?


Thanks!

speedball1

2) put shower base (w/ drain installed) down onto concrete (do I need to put some mortar or anything down below this?)

If the base has no support and "gives" a bit when you put weight on iut then I would bed the base at the time of installation.
My expertise stops at the plumbing end so I'm kicking this thread over to experts that have more knowledge the I. Regards, Tom

dclynch

3) - You should put a vapor barrier behind the cement board. 6 mil poly sheeting works well. It should overlap the lip of the shower base. The cement board should extend at least as high as the water will likely splash - about six feet. The cement board seams should be taped and then "mudded" with thinset. They make special fiberglass tape for this. It is heavier duty than the tape for drywall. The taping can be done in advance or at the time of installation. If done in advance, be sure to avoid creating a "speed bump." Only use dry mix thinset. Do not use mastic or premix thinset in a wet area.

6) Many people also suggest caulking the corner joint. You can grout, but be sure to keep an eye on it over time, as this is a place grout can fail.

Good luck.

mtnbkr

Thanks for the info. For the 6mil poly sheet, do I just staple to the studs, then hang the cement board over it? Then just make sure the edge of it hangs over the shower base...should I caulk it down or something?

dclynch

Stapled to the studs is fine. Put the cement board up over it. After tiling, you can trim the excess before caulking the base-tile joint. (Or you can trim earlier, doesn't matter.)