replacing wall tile around bathtub - any suggestions welcomed

[riccet]

Does the following look like like I have my bases covered? Should I paint the wallboard behind the shower enclosure? Should I put some other sort of membrane between the wallboard and shower enclosure?

House is 60yo and it looks like original wall was a cement covered by tile (ugly pink - glad to see it go . A repair was made over 35 years ago where they built up the studs to mate 1/2" white wallboard to existing 3/4" wall two feet up around tub.

My plan is to rip out all of wall and replace with green board and put a plastic (we're poor) shower enclosure over top of the wall board. The tub mates against the studs with an upward curl. The wall board will mate against that top of curl, then I will fill in that curl completely with silicon based sealant which will seal bottom of wall board.

 

[Jadnashua]

Had typed in a reply and it got lost...bummer.

Don't use the greenboard, it's basically junk and is no longer in the national codes (maybe not adopted by local yet) for much of anything...there are much better and reliable products. Tearing out the old mudbed walls (floated walls) is messy, the metal lath in it is sharp, and the stuff is heavy. It does make a nice wall to tile on, though. You'll probably find on an old house that the studs are not very even, and are HARD. You may need to predrill.

You need a moisture barrier on the studs (plastic sheeting or roofing felt) lapped over the tiling flange of the tub, then cbu (cement board) if you want it to last. Use real thinset, not the stuff in a bucket - it's cheaper and will last. The mastic (even though sometimes the bucket says thinset, it's not) never cures like the cement, and will soften and can even wash away if it constantly gets wet.

Check out www.johnbridge.com for help with tiling...they'll take good care of you.

 

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[riccet]

Thanks very much for your response!

Had typed in a reply and it got lost...bummer.

Yeah, I hate that. Sometimes, I remember and use notepad or kate, but the norm is for me to lose it...

Don't use the greenboard, it's basically junk and is no longer in the national codes (maybe not adopted by local yet) for much of anything...there are much better and reliable products.

I'll find out tomorrow. This is a temp remodel. If I ever live here, I'm gonna toss the tub and push the wall out a couple of feet.

Tearing out the old mudbed walls (floated walls) is messy, the metal lath in it is sharp, and the stuff is heavy. It does make a nice wall to tile on, though. You'll probably find on an old house that the studs are not very even, and are HARD. You may need to predrill.

Lots of black mold, but no structural damage, thank the Lord!

You need a moisture barrier on the studs (plastic sheeting or roofing felt) lapped over the tiling flange of the tub, then cbu (cement board) if you want it to last. Use real thinset, not the stuff in a bucket - it's cheaper and will last. The mastic (even though sometimes the bucket says thinset, it's not) never cures like the cement, and will soften and can even wash away if it constantly gets wet.

I'm just trying to figure out the cheapest solution that will last a while. I was originally attempting to put in some hand rails and accidentally push my hand through a rotten part of the wall. That's good in a way because I can now mount the handrails properly on facial boards.

 

[riccet]

Well, the story I get from my local code compliance is that I can put anything up around my tub as long as I do not create a moisture lock. They are happy if I follow the manufacturer's directions for the product I will install. And the manufacturer recommends plain drywall. So be it.

 

[Jadnashua]

Putting drywall behind the tile of a shower is not bright. Now, if it is only a tub, and no shower is involved, it may survive. Paper is good mold food, and all it takes is a little moisture. People tend to think tile and grout is waterproof...maybe under perfect situations, but not in practical situations...the grout, even when sealed, still will absorb moisture. Code requirements are minimums, and often only address safety, not longevity.

 

[riccet]

Putting drywall behind the tile of a shower is not bright. Now, if it is only a tub, and no shower is involved, it may survive. Paper is good mold food, and all it takes is a little moisture. People tend to think tile and grout is waterproof...maybe under perfect situations, but not in practical situations...the grout, even when sealed, still will absorb moisture. Code requirements are minimums, and often only address safety, not longevity.

This is getting a little frustrating, I'm talking about apples and you are talking about oranges, while at the same time telling me my apples are no good. You mention there are pears, but you don't give me any specifics. I have been googling for several days and all I can find is apples and oranges. How do I search for the pears if I do not know what they are? Isn't a purpose of this forum to help me find the pears?

 

[Fistor]

Hi riccet -

Sounds like your old house is similar to mine (mine was built it '52) - the bathroom had that old-school cement-type wall material, which I broke out in chunks.

Anyway, I took it all out, and am about to use cementboard beneath the tiles, which will extend to slightly above the showerhead. I am using greenboard everywhere else.

I think that at least for the tiled section you should use the cementboard as he suggested, and from what I can tell, it's not prohibatively expensive. (The screws for it seem a little costly, but you want to do it right).

That's what I plan to do, might be worth considering for your case too.

 

[Jadnashua]

I'm not sure how much clearer I can get, putting drywall or greenboard in a shower is not good (unless you put a waterproof membrane over it, but you don't seem to want to go there - it is a premium install)! The greenboard only has a water resistant covering that you put nails or screws through, creating lots of holes that will let water get inside it. CBU doesn't degrade if it sits immersed in water constantly. Regular drywall's paper covering gets wet, feeds mold and makes a mess. Both lose structural strength when they get wet, which is almost certain on the lower edges and section that gets hit by spray and splash on a regular basis. Regular drywall is the preferred material outside of wet areas...greenboard's covering lets the stuff bow or sag more than regular drywall, and if used on a ceiling, needs support at 12" rather than the 16" of drywall...there is no good technical reason to use greenboard anywhere unless your local codes have not been updated to the latest national standards. If you want it to last, you need to use cbu (cement backer unit...aka cement board). Industry practice also calls for a vapor barrier behind that (on the studs) lapping over the tiling flange of the tub.

Will drywall last a few years...probably, especially if you use your towel to wipe down the walls and tub edge after every shower. Do many people do that? No. In a frequently used shower, it could fail in a year, or it could last a number of years. Somewhat depends on if the tub is still level and where water pools.

Before greenboard, drywall, and cement board, they put up lath and a mortar bed on the walls. It made a great substrate for the tile, takes a lot of skill, and is slower than using cbu. It is still done, and creates a superior result if done right, but not that many people can still do it...sort of like getting someone to do real plaster walls...you can find them, but it's tough.

 

[Frenchie]

He's not putting up tile - he's putting up a plastic surround.

That said, I'd still recommend wonderboard instead of drywall - unless it was the paperless type, maybe.

 

[Wrex]

FYI the cement you have behind your tiles is the old way bathroom tiles were held to the studs. Metal lathe is nailed to the studs then mortar was applied to the lathe then tiles were applied on top of that. Its called a mortar bed.

Think of it as the modern equivalent of cement backer board.

By the way cement backer board is ALWAYS the way to go in wet environments like the shower. Also as previously suggested you want a vapor barrier behind the cement board.