I’m tiling a lath plastered wall for my shower. The wall is far from perfect. How flat does the wall have to be? For example, if I place a 4′ level against it, what is the max space between the wall and the level that would be allowable?
I am using a cement based, non-flexible, water resistant tile adhesive on 8″ x 12″ tiles.
Any input would be greatly appreciated.
Thanks.
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Replies
You've got problems.
First, shower tile should be installed over a cement board with a membrane behind it so water leaking through does not cause damge to the structure or finishes in floors below. There are some polished plaster jobs that would probablu repell more than 99% of water though, but I doubt they would be an uneven plane, so I assume yours is quite permeable. Best to break inbto the wall to prep it right.
Then no more than a sixteenth of an inch in a foot or an eighth overall would be the max of undulation I'd want. The larger the tile size, the more the flaws will show.
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save yurself a great deal off effort and later headaches and replace the wall with a CF backer board... (Hardie make a good one..)
are you using thinset??? if not, you should be...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
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Forget the primal scream, just ROAR!!!
Well, first off folks are gonna tell you to not do that -- they'll tell you that you need to rip out the plaster and install cement backer.
But in terms of flat, you're using too long of a level. You want one closer to 2 feet long (ie, on the order of twice the size of a single tile), and hope to not see more than about 1/4" under it (assuming you're using "thin-set" and not mastic). But with the longer level you'd check to make sure there are no serious 3-dimensional humps or bowls that would upset the spacing between tile.
My plan was to paint the wall with water based polyurethane as a moisture barrier (it has held up well on my floors), and to use an adhesive (Bond-It CTA White tile adhesive) that bonds to polyurethane and is water resistant. I was figuring that, and a little silicon in the corners, would take care of the water problem. Still a bad idea?
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Thanks for the input.
yup...Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
I'm not the expert. But if it was me and I wasn't investing in really expensive tile, and I knew to keep an eye out for signs of leakage, I'd be inclined to give it a shot (though might skip the polyurethane).But there are a lot of factors involved. If this was already a shower area, and was plastered for that purpose, likely the plaster used was pretty moisture resistant. If use will not be "abusive" then it's a pretty good bet. OTOH, if you're installing a shower where there wasn't one (at least not regularly used), and it will be used by three teenagers, you want an approach that's armor-plated.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
Mabe - depends on how solid the plaster sub is and how prone the house is to moving, seasonally or otherwise, and depending on what is under this shower to get damaged or resist mold when it gets wet.Sounds like you need to skim coat anyways. If everything else is tight and solid, I might be tempted to skim it witha hydraulic patch cement such as used on basememnt walls.but I'm fairly good with a trowel. That stuff sets fast so you could end up making a mess of things if you don't polish it in quick.
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water based polyurethane as a moisture barrier (it has held up well on my floors),
Evidently you are quite confident that you could turn a garden hose on your hardwood floors for twenty minutes each morning, then cover them to prevent evaporation (like the plaster layer will do), and have no resulting problems over the next twenty or so years.
Dude, call a pro.
Today.
You're so far from knowing what's what, that you're gonna cost yourself huge bucks.
Unless you're the lead dog, the view just never changes.
There is a bible to consult ... the TCA Handbook - http://www.tileusa.com/publication_main.htm. If you find your existing conditions in there you will also find out what is required for a quality tile installation.
Jeff
Is this an existing shower stall, or are you adding some plumbing to an area that previously had none?
If it is already a shower, hten there is good news and bad. The walls are probably already waterproof -- but the (probably quite old) shower pan can'g be in very good shape.
If it's not already a shower, then the nature of your question implies that you are in WAY over your head.
Unless you're the lead dog, the view just never changes.
Could you give us a more complete picture of your project? Are you adding a shower/tub to a new space, or tiling a shower/tub area that was already there, and you are just tiling the walls? Have you ever done tile work before? Is your wife pestering you to get this done, and you have already laid out a game plan and now the gang here is making you wonder- what did I get my self into?