# Forum Home Renovation Waterproofing  Waterproofing Method for Brick Walls and cement render

## DaleBlack

Water Proofing Technique and Materials 
Situation: Brick wall with cement render and whiteset plaster. Though that whiteset plaster as per another thread I have going here will be either completed removed or 50% chipped away. 
I also need the existing screed with small rectangular tiles on it to be ripped up so the floor in the bathroom can be at the same height as the woodfloor in the adjacent room.
The walls will then be primed. 
At this point I need to complete the waterproofing prior to tile adhesive and tiles. 
Is the following a correct method: 
Apply a bond breaker to all vertical and horizontal joints including hob. Seal
all penetrations     *Q:What Sealant? can anyone recomend exact brands, I realise you should keep within a system*  Silcone orPolurethane orCo-Polymer Sealants    Comparing Silicone Sealants With Polyurethane Sealants | Maxwell Supply Blog 
The above site seems to indicate silicone is superior with a 20 year life vs polyurethane.  Co polymer only catches my eye as I saw this    Co-polymer sealant also resists mould. This ability makes it ideal for basements and other damp areas of the home where mould can grow.  https://www.austinwaterproofing.com....roof-sealants/    Also some people also seem to recommend a compressible backing rod instead of a sealant? 
Extent of waterproofing  requirement:  
A) 
Entire shower recess floor, ensuring membrane is carried into the puddle flange to a minimum of 20mm. Puddle flange will require a light sand to key the surface, prime flange with the appropriate primer eg. "Plumbers Mate" Priming fluid red, before waterproofing. 
B) 
All vertical and horizontal joints should be incorporated with waterproofing tape *Q:
I was told some in the trade consider this a double up? As the bond break (the sealant) has already gone in as described above, so using the tape as well could be seen as excessive ??* 
C) 
All walls to rose height in shower recess 
D) 
Entire floor areas outside the shower recess
E) 
Waterproof all wall and floor junctions including door frame.40mm above floor level, incorporating a bond breaker and tape  
Tiling: Wall over floor tile with silicon bottom grout joint. Silicon should also be applied to all vertical interfaces in shower recess 
Recommended ratio of fall within a shower area is between 1:80 to 1:100. Recommended 
ratio of fall in other wet areas is 1:100 
NOTE: 
Best practice is to waterproof under screed and over the Screed  *Q: is it worth waterproofing under and over the screed?*  
Any comments and in particular images and recomendations of a system is appreciated.

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## rebuildr86

ok u might be overthinking it all.
Where exactly are you, is this a well settled WA house by any chance?
If its bricks on slab and well settled, bond brakers and tape is a ridiculous waste of time.

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## DaleBlack

> ok u might be overthinking it all.
> Where exactly are you, is this a well settled WA house by any chance?
> If its bricks on slab and well settled, bond brakers and tape is a ridiculous waste of time.

  Hi rebuildr86 - yes this particular work is a WA house, of a relative. Its late 70s double brick on slab. 
Are you saying not to use a sealant or tape? how do you do it?

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## rebuildr86

so over here, we are on sand dunes, and after about 5 years, and definitely by 10 years, all settling has basically finished. For this reason, for almost any WA bathroom renovation, u can just brush the membrane up to the corners.
DO not waterproof above and below screed as this will trap the moisture in the screed.
I recommend screeding early then waterproofing on top of the screed and down into the waste pipe. This gives the best runoff and prevents mouldy grout and silicone.
For silicone, if you are going white, use nothing other than selleys white for life silicone, however, be sure not to let it touch and of the waterproofing membrane as it is an acetic cure silicone and can damage the membrane. So if u have big lines to silicone, fill them first with an acrylic gap filler with mould inhibiters in it (kitchen ad bath no more gaps) thne wait for that to cure before aplying the silicone.

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## DaleBlack

> so over here, we are on sand dunes, and after about 5 years, and definitely by 10 years, all settling has basically finished. For this reason, for almost any WA bathroom renovation, u can just brush the membrane up to the corners.
> DO not waterproof above and below screed as this will trap the moisture in the screed.
> I recommend screeding early then waterproofing on top of the screed and down into the waste pipe. This gives the best runoff and prevents mouldy grout and silicone.
> For silicone, if you are going white, use nothing other than selleys white for life silicone, however, be sure not to let it touch and of the waterproofing membrane as it is an acetic cure silicone and can damage the membrane. So if u have big lines to silicone, fill them first with an acrylic gap filler with mould inhibiters in it (kitchen ad bath no more gaps) thne wait for that to cure before aplying the silicone.

  cheers for your response, can i ask what exact system you use 
Brand and Model of 
Primer (assume you apply over the cement render with whiteset removed(based on your answer in the other thread) _Bond Breaker Sealant - delete 
Tape - delete_
Waterproof membrane
Tile Adhesive 
I was told to be sure that the primer, waterproof membrane and adhesive can all work with each other. Also on the tile adhesive, one shop made a point of not just a straight cement based adhesive but one with polymers that supposedly resists vibration more due to its flexibility over pure cement based tile adhesive?

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## rebuildr86

I use gripset beta membrane, available at bunnings, and i apply it straight to cement render.
For walls, davco powder mastic tile adhesive.
Floors, ultraflex adhesive
There are very few pure cement adhesives, no one uses them.

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## DaleBlack

Is it also important to ensure a puddle flange is put in like the below video

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## rebuildr86

We dont do that in WA. At least not on concrete slabs on ground floor. Just continue the waterproof membrane down the pipe a bit

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## DaleBlack

Hi are you sure, I ended up finding/being directed to this 
WA abides by the NCC standards, these standards require you to use a  puddle flange as is stated in AS 3740, from what I have read puddle flanges are a basic requirement  in all wet  areas as stated in the NCC which WA has abided by since mid 2015. 
they install very easily and guarantee a leak proof connection at the  most critical point of the floor, use one in the shower recess and floor  waste. 
Some WA relative documentation below.  https://www.commerce.wa.gov.au/sites...iles/ib_61.pdf

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## rebuildr86

Nah im aware of the regulation, but a renovation is a bit different.
Go ahead and spend days chipping away concrete and fitting a flange and reconcreting for the same result as leaving whats there the hell alone haha.
There is no problem just waterproofing the pipe. On an old well settled concrete slab at least.

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## phild01

I don't see a problem dismissing the puddle flange if waterproofing is thoroughly addressed at the waste of a concrete floor, especially if a termite collar exists.  A product is invented and it's use gets mandated!

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## rebuildr86

well i have a theory that the puddle flange could even potentially be problematic in some cases.
if it is done absolutely perfectly and a lot of attention payed to preparing it, measuring the recess and all that, it may be ok, but its likely that it will jsut creat more problems where the membrane has to change thickness as it jumps over from concrete to plastic. Thisresults in a thicker secion of membrane, which is actually a failure point.
Deburr the pipe and make sure the membrane is done libberally and uniform and there will be no problems.

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## DaleBlack

> well i have a theory that the puddle flange could even potentially be problematic in some cases.
> if it is done absolutely perfectly and a lot of attention payed to preparing it, measuring the recess and all that, it may be ok, but its likely that it will jsut creat more problems where the membrane has to change thickness as it jumps over from concrete to plastic. Thisresults in a thicker secion of membrane, which is actually a failure point.
> Deburr the pipe and make sure the membrane is done libberally and uniform and there will be no problems.

  I wondered about what you wrote here and this video seems to confirm the issues with puddle flange installs where the person doesnt do it properly. It undoes all the previous work. The guy also talks about people paying  more for a top and bottom of screed water proofing membrane but the flange isnt installed correctly

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## DaleBlack

the above video, Rebuilder86 appears to have the non flange method you mention discussed on the 2nd from the left example i assume not the one on the far left where the pipe wasnt flush 
How do you ensure the drain grate doesnt sit tight into the drain pipe blocking any water, the issue he mentions

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## rebuildr86

Every drain grate ive installed has been so loose in the pipe that its not an issue. I stuff them in with lots of glue in the 4 corners (of a square one) and make sure there are little gaps in the glue on each flat side so that any moisture that gathers near the drain can get into the drain fast.
Most ppl smear the glue around the entire thing, but the glue is pretty water resistant so thats not a good iead.
For round ones, i put blobs of glue at 33 degrees around and push it in.

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