Waterproofing walls

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Posted by: from Toronto
3/25/2008 at 2:32:30 PM

I am re-doing my bathroom. From top to bottom. I am putting in a clawfoot tub. I am asking about waterproofing walls. I realize that you need to waterproof the walls around the bathtub and shower (there will be a separate shower stall with tiled walls). Since the clawfoot tub won't be up against the walls, as other tubs do the walls still need to be waterproofed?

If they do, what can I use? I really don't want to tile around my clawfoot tub. I think that will look odd.

Currently, I do have some concrete drywall - I don't know what it's actually called, my father-in-law got it for us. Is that enough? Can I paint over that? It's not a smooth surface.

Any ideas/help would be greatly appreciated.

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In Home Details in Guelph
Date/Time3/27/2008 at 4:05:25 PM

You are right, cement board (which is what is often used in bathrooms because it doesn't attract mould easily) is very rough. Depending on how rough the surface is, I have put on a skim coat of drywall mud, just to smooth out the bumps. However, that was only ever on a small section of a wall -- not the entire wall. But you could skim coat the whole wall, if you don't like the way the cement board finishes with just paint.

And unless you are planning on a lot of baths where you splash the walls with water all the time, I wouldn't tile -- just keep the splash factor down.

But I know other people will be able to contribute other view points.


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Date/Time3/30/2008 at 8:23:12 PM

In rooms such as the bathroom that experience significant moisture there is a drywall sheet specifically designed for that use. Some call it "waterboard", it is readily available at supply stores and is usually green in color. The cement board that you have now is for areas that have actual contact with water, like in your is generally used as an underlayment for tile or a concrete overlay application. Use your cementboard in the shower and get some "waterboard" for your walls around the tub. Good luck.

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Date/Time5/28/2008 at 11:00:20 AM

I agree with Trevor to some extent. You should us a product that is used for damp areas although i prefer to use a completely waterproof product rather than a water resistant product. There is a significant difference in the terms "Water proof" and "water Resistant"

Water Resistant products are ment to only help in damp areas and at some point can grow mould.

A Water proof product should not .

DensArmor Plus is a paperless drywall product by Georgia-Pacific. I think home depot carries this product.

Mould grows because if feeds on the paper in the drywall. using a product like the DesArmor in highly wet or damp areas can reduce the risk of mold significantly.

this is a more expensive product but at 2 or 3 times the cost per sheet . if you only use 3 sheets the cost isnt that much more.

You still have to finish it with something on the surface though.

If you are not proficient with a trowel and drywall mud i don't suggest you try to skim the surface yourself as it is a hard skill to master.

Hope this helps..

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Date/Time2/24/2009 at 11:33:25 AM

Well it depends on what proximity your tub is to the walls. If it is relatively close and you expect water contact, than I wouldn't recommend the "water resistant" drywall, and would look into more expensive water proofing methods. On the other hand, if you have atleast 2feet open space to the nearest wall, and you are trying to keep the budget down, than I wouldn't discourage you from using a "water resistant" drywall as it is less work to prepare it for paint. However, I do recommend good ventilation to remove any moisture. And keep in mind that a good quality bathroom paint will help act as a vapour barrier.

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