Brick & Block / Concrete Floor - Do I need to tank?

[jay]

Hi m8

First off its not advice its an answer to the question the man is asking given the situation. Generally on new build concrete walls I wouldn’t push tanking as solid walls are rarely suceptable to joint fracture as dry wall carcassed walls are. Solid walls stand a lot longer and have infinitely more time to move during the drying process. On an old property where decay has taken place then the answer would be yes inorder to stabalise the surface that may be cracked or damaged.

The majority of water ingress derives from cracking at transitions, that is corners and wall to floor points not through grout line failure. The ingress as its spoken of is water leaking at transitions and moisture penetration at grout line. The latter is a concern obviously but moisture ingress predominantly goes through the drying out process during shower down time where as leaks are leaks.

There are all kinds of reasons lent to why you should tank but the main one being “ to secure a wet area so preventing water damage to surroundings due to substrate failure “ and is directed at dry build systems and the problems that can arise from leaks into floor voids, electrics etc where tanking is a must.

Back to the question, the room in the picture has its corner block work bonded so if it moves it will all move, and there is no direct strike area. Later we are advised that the floor will be the strike area as the shower head is ceiling and central.

Looking at it from here I would say fix Dura-CI before your tiles over the poured screed, as it appears the drop in the floor will not be brought to level and possibly hold water tape the wall floor transition. As for the walls they are to be rendered, then covered in adhesive then tiles and grout tanking imo will not be of benefit, if you want belt and braces put waterproofer in the render.


Hope this helps a little.

can see were you are coming from and tend to agree on some // but if your going to do this sort of a bathroom and you want to eliminate all possible future problems ( moisture in blockwork poss leaks bacteria growth slower floorheating pos efflorescence in grout ) for the few extra dollars i would waterproof and have peace of mind but that's me if you do go the waterproofing or tanking way you cant beat wet dec
:8:

 

[wetdec]

if your going to do this sort of a bathroom and you want to eliminate all possible future problems ( moisture in blockwork poss leaks bacteria growth slower floorheating pos efflorescence in grout ) for the few extra dollars i would waterproof :8:

Well then lets tank the ceiling incase we get a hole in the roof......:smilewinkgrin:



..

 

[grumpygrouter]

Well then lets tank the ceiling incase we get a hole in the roof......:smilewinkgrin:



..

....business opportunity, prior to laying insulation?????

 

[jay]

Well then lets tank the ceiling incase we get a hole in the roof......:smilewinkgrin:



..

good idea
if it was your bathroom wet deck you wouldn't tank or waterproof
if it was mine i would



once tiled if a problem occur es and only if do you patch and hope for the best or rip it out and start again didn't realise he wanted to tile ceiling:lol: