Waterproofing before tiling - TilersForums.com

[sarahjane13]

Hi. I've just had the bathroom re-plastered and will be tiling soon. We have a shower above the bath and are wondering about what to use to waterproof before tiling. The plan was to use the mapei waterproofing kit on the walls (but not the tape as from what I've read this can peel off the edge of the bath after a period of time) and then use the mapei keraflex adhesive. Is this actually necessary or could I just use mapei primer for plaster and tile straight on. The tiles we took off recently didnt have any waterproofing under them and everything was dry. I'm not sure of waterproofing is necessary for a shower over a bath or just on shower cubicles. Thanks

 

[Dave]

Please contribute to this thread if you have any new information or can even just reiterate what has been said already.

Hi. I've just had the bathroom re-plastered and will be tiling soon. We have a shower above the bath and are wondering about what to use to waterproof before tiling. The plan was to use the mapei waterproofing kit on the walls (but not the tape as from what I've read this can peel off the edge of the bath after a period of time) and then use the mapei keraflex adhesive. Is this actually necessary or could I just use mapei primer for plaster and tile straight on. The tiles we took off recently didnt have any waterproofing under them and everything was dry. I'm not sure of waterproofing is necessary for a shower over a bath or just on shower cubicles. Thanks

Hi. It’s personal choice , tanking offers a belt and braces approach but it can be tiled without no probs. If it was a shower cubicle then I’d say yes tank as water ingress usually starts around the bottom area but in a bath not so much.
Make sure you have a good silicone seal between the bath and the wall and the bath is fully supported, especially in the corners to prevent excessive flexing of the bath under duress. Then another silicone seal between tile and bath and internal corners.

 

[sarahjane13]

Please contribute to this thread if you have any new information or can even just reiterate what has been said already.

Please contribute to this thread if you have any new information or can even just reiterate what has been said already.

Hi. It’s personal choice , tanking offers a belt and braces approach but it can be tiled without no probs. If it was a shower cubicle then I’d say yes tank as water ingress usually starts around the bottom area but in a bath not so much.
Make sure you have a good silicone seal between the bath and the wall and the bath is fully supported, especially in the corners to prevent excessive flexing of the bath under duress. Then another silicone seal between tile and bath and internal corners.

Thank you for your response! I'll be building a wooden frame/support for the bath to ensure it's well supported and avoid flexing and sealing everything with silicone. I'm leaving more towards juat using the primer ad I did this in my last house and it was fine and I never had any problems.
Just one other question...my current plan is to install the bath first and then tile from the top of the bath upwards. Is this the best way or am I best either (a) tiling the full wall then fitting the bath, or (b) attaching a baton to the wall at the correct height so the bath can rest on it, then tiling, then sitting the bath on the baton so the tiles go down past the edge of the bath by a couple of inches? Thanks again!

 

[Dave]

Please contribute to this thread if you have any new information or can even just reiterate what has been said already.

Please contribute to this thread if you have any new information or can even just reiterate what has been said already.

Thank you for your response! I'll be building a wooden frame/support for the bath to ensure it's well supported and avoid flexing and sealing everything with silicone. I'm leaving more towards juat using the primer ad I did this in my last house and it was fine and I never had any problems.
Just one other question...my current plan is to install the bath first and then tile from the top of the bath upwards. Is this the best way or am I best either (a) tiling the full wall then fitting the bath, or (b) attaching a baton to the wall at the correct height so the bath can rest on it, then tiling, then sitting the bath on the baton so the tiles go down past the edge of the bath by a couple of inches? Thanks again!

Fit the bath first , it creates a better seal as bath edges can be chamfered, creating a wide silicone joint.

 

[Tony73]

Hi. As above , you don't have to waterproof above bath. Personally, I always waterproof above bath, then seal between bath and wall, with silicone, then tile , grout and seal with silicone bath -tile, and tile-tile internal corner.

 

[Kevbos]

Hi. I've just had the bathroom re-plastered and will be tiling soon. We have a shower above the bath and are wondering about what to use to waterproof before tiling. The plan was to use the mapei waterproofing kit on the walls (but not the tape as from what I've read this can peel off the edge of the bath after a period of time) and then use the mapei keraflex adhesive. Is this actually necessary or could I just use mapei primer for plaster and tile straight on. The tiles we took off recently didnt have any waterproofing under them and!all into a drain then everything was dry. I'm not sure of waterproofing is necessary for a shower over a bath or just on shower cubicles. Thanks

There is no point waterproofing walls down to Bath edge !as the place thar water will penetrate is usually at that point !! And unless you waterproof the walls below and the floor below , then all you will achieve is pushing a problem where it can't be seen until its damaged alot !!