[everyman]

Hi,

I have a couple of bathrooms under renovation (for months now ). I ended up replacing about 80% of the drywall with 1/2" Hardi. Basically the only drywall left is about half the ceiling and the top half of the farthest wall from the shower. I did the part of the ceiling because I'm going to tile the entire shower box. I did add all of the required extra framing to support it. I couldn't believe how many 2x4's I went through doing all of that. It would have been really nice if they could have seen fit to provide the material in a 4x8 size.

So this is the point I'm at now, and am trying to get the next step straight. There are of course many seams since I had to use so many chunks of the board, and I'm wondering how this is meant to be accomplished. From their instructions it appears that I'm supposed to use the special mesh tape, and just plain tile mortar, is that right? My concern with this is that tile mortar sets rock hard. This isn't really an issue on the shower walls and tile wainscoting I plan to do, but if I was to use that on the area of the walls which is to be painted, it wouldn't be too easy to sand it flat once cured. Should I just do those seams with drywall compound?

Also which seams should be sealed with silicone first? I'm a bit concerned about that step as well because it seems like any silicone that got on the wall area would interfere with the ability of tile mortar to adhere. Should I also use that around the holes I cut for the plumbing fixtures to come through?

One last question, I did my best to use the nubby side of the material where the tile goes, and the flat side where it will be painted, but there is some overlap. Should I hit the area to be painted with a belt sander lightly to smooth it out? I know you aren't supposed to use power tools on it indoors, but with a shop vac connected to the sander and a respirator, I'd imagine I could cut out most of the dust problem.

I lied, I do have one other question. I had planned to install a couple of small tile corner shelves in the shower area. Are those meant to be completely supported by tile mortar? There are a couple of casting holes on the back of the things which go all the way inside them. Should I figure out a way to put some dowels or bolts or something into the wall that would help to support them? It seems like the first time someone put anything heavier than a bar of soap on them, they might break free which would really stink.

Thanks!!
Eric

 

[RDS]

You plan to paint some of the cement board? I'm far from an expert (bathrooms remodeled: one) but I have never heard of this. Why not use drywall in those areas? I realize it would involve undoing work you've already done, but it seems more suited to paint.

Hopefully pros will weigh in on this and your other questions.

 

[LeviDIY]

Agree with RDS - green board on the non-direct water areas would be fine. I'd imagine you need a lot of sealer/primer/Zinsser! on the CBU to make it paintable.

Tile corner shelves: these are not meant to be safety grab bars... they will hold shampoo bottles and soap, etc if installed with thinset/morter in those grooves and along the CBU, then caulked around. When setting it, I used some painters masking tape to hold it in its place while the thinset cured for a few days, then grouted, sealed and caulked for good measure.

 

[everyman]

Agree with RDS - green board on the non-direct water areas would be fine. I'd imagine you need a lot of sealer/primer/Zinsser! on the CBU to make it paintable.

Oh dear. That's not good. That would be a huge job to redo. It's a real pain to match the CBU thickness to the drywall. I was spending an awfully long time shimming out the CBU in the areas where I did seam it to drywall. I'm going to have to give this a great deal of thought before replacing it. Maybe give the painting a try.

Tile corner shelves: these are not meant to be safety grab bars... they will hold shampoo bottles and soap, etc if installed with thinset/morter

Ah okay. I guess I'm just paranoid. I usually think you should be able to do chinups on everything