# Forum Home Renovation Tiling  Re-tiling shower on rendered brick walls

## deepersley

Hello, I'm fairly new here and finding the info on this forum so valuable for my many half finished renovating projects. 
Anyway I'm having a go at our en-suite at the moment, nearly finished gutting it, but I'm having doubts about what to do with preparing the walls in the shower for re-tiling which are rendered brick. 
The shower had leaking problems at the floor/wall joins and also quite a few tiles were cracked, presumably from the render cracking behind them.  When removing the tiles, large chunks of the render have come off and also the old waterproofing near the floor is very hard to remove. 
Instead of trying to clean up the render and patch up the missing bits, I was thinking of attaching villaboard to the current render or removing all the render and attaching villaboard to the brick.  I was wondering if this is something that is recommended or what anyone else has done is this situation? 
cheers

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## Batpig

Dear Deep, 
I'm not so sure that a patching-up of the current coat of Render would be any more difficult than stripping it all off and then attaching Villaboard... 
If you want to just patch-up the current Render, I would: 
1) Keep going with either your cheap little Ozito Rotary-Hammer in chisel-mode to knock off the rest of the little bits of white tile that you can see here and there in your photo, or use a Club-Hammer and a Brick-Bolster or Cold-Chisel to do the same thing by hand. Check for "drummy" bits of Render while you're at it, and remove them too... 
2) Using the same method, knock off the water-proofed bit of Render down around the bottom right back down to the brick. 
3) Give the whole Recess a good going over with a Dustpan-type brush in order to remove any surface dust. If you don't mind indulging in a little bit of "overkill", bring your garden hose in and give the whole thing a spraying over (have the Mop and Bucket handy, though... :Tongue: ) 
4) Go to the BigB and grab yourself a bag of pre-mixed Render powder. Whatever the brand, it's usually Acrylic-modified to make it stick a little bit better to the substrate. While you're there, also get yourself a rectangular Cement Trowel. 
5) Get a little plastic tub and an old Paint-Brush, and mix up a solution of, say, 50/50 Bondcrete or Aquadhere to Water. You'll probably need about a litre to do all of the repairs. 
6) Get a small trigger-action pressure sprayer and give a few of the bare-brick patches an advance spraying of just plain water. 
7) Mix up a small Saucepan's worth of the Render with water, until you get a thick creamy consistency. 
8) Pick a patch that needs doing, and when the moisture from 4) above has soaked in to the brick, give the brick a good painting with the Aquadhere/Water mix. 
9) While the Aquadhere/Water coating is still wet, scoop some Render up out of the saucepan with your Trowel, and slap it onto the brick. Then flatten it out as best you can by using the intact Render on either sides of the missing patch as "formwork" shoulders with which to guide the Trowel. 
10) Don't be too worried if you can't get the wet Render perfectly flat to begin with. Lean your Trowel over forward quite heavily when you first level the Render while it's still very wet. In about an hour's time when it has got a little bit of initial "set" to it, you can come back and "shave" it by running the Trowel over it again, but with much less forward lean on the face of the blade. Because you're going to shave it later, getting it to be ever-so-slightly "bulgey" out from the surrounding dry Render is a pretty good way to go. 
11) For the continuous strip of brick down the bottom where the old Waterproofing was, use the unremoved Render just above this as a guide for your Trowel (which will be cantilevering down from it...) You will therefore be running the Trowel left-to-right in that area, rather than up-and-down for the other patches. 
12) As said in 10) above, check the patches you've done periodically until you notice that one has started to set, then "shave" it flat with your Trowel. 
13) Repeat the whole process as you go - ie. Spray with water, allow water to soak in, paint with Aquadhere/Water mix, slap on Render, flatten, allow to "set", then shave down to level of surrounding surface. 
If you are really lazy, you could delete the use of the Aquadhere/Water mix, but not the spraying with the plain water. Otherwise, the Render will just fall off the wall each time you slap it on... 
If there are some very shallow gouges that haven't gone all the way down to the brick (say only a millimeter or two deep), you'll be better off leaving them to the Tile adhesive to level out, rather than to frustrate yourself trying to get the Render into them and stick. 
That's all I can suggest for now. It would certainly be a less expensive exercise than adding Villaboard... 
Best Wishes,
Batpig.

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## GeoffW1

Hi, 
Agree with Batpig on all that. What we then did for waterproofing the floor to wall join on our renovation was to attach a plastic angle with Sikaflex. The render surface to the height of the shower screen, plastic angle and flooring of the shower was then coated with a waterproofing membrane like Gripset 38. The tiles went over this.  http://www.gripset.com/handyman/product.php?productid=5  http://www.crommelin.com.au/pdfs/showerwpmembrane.pdf 
Another way is to place a copper or stainless shower tray in place before tiling. 
Cheers

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## deepersley

Thanks for going into such great detail Batpig, you've sold me on the re-rendering.  I was picturing myself slapping on the render and it sliding straight off, but I think I can pull it off using your instructions.
And thanks for the waterproofing tips Geoff, its one of my main concerns as both our showers are leaking at the moment after multiple attempts to fix them, the plastic angle sounds like a good idea.

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