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

[Ripmaster]

Take on board all the comments as they are all relivant experienced opinions.

My answer would be no.......

..

Thanks wetdec, would you mind expanding as to why you think no. I'm curious as your are the first to agree with my builder on this - He'll have a field day as I'd told him all the advice I received so far as to tank - I'm just keen that the job is done properly so would appreciate your thoughts.

Thanks again for taking the time.

 

[DHTiling]

I would tank.. constant wetting of the substrate can cause damp to travel and is a haven for mould spores...

It is better to just have the adhesive bed getting wet , rather than the whole substrate ,be it concrete floor or block walls..

I know what my preference would be.

 

[White Room]

Tend to agree with Dave, with the render being strong but brittle if there is any movement/settling down in the subtrate it will travel thru to the tiles.

 

[heavytrevy]

lmao,

Water will easily go thru the blockwork.
I seen plenty without tanking and the resulting water stains and mildew on the other side is pretty bad.

I would tank above the height of the rose , use a liquid tank , ardex make good ones.


i can link you some detailed waterproofing instructions if you like.
you will need bondbreakers in all the corners and of course a waterstop at the doorway.

Trev

Take on board all the comments as they are all relivant experienced opinions.




My answer would be no.......


..

 

[Ripmaster]

Hi Trev, any links greatefully received...

I assume you mean the doorway to the shower area, rather than the doorway to the bathroom. The shower is nowhere near the entry door to the room and is sunken into the floor so would need to fall asleep and block the drain to cause enough of a flood to reach the door I would have though :yikes:

 

[heavytrevy]

Both , only takes a washcloth or a block of soap .


Im off to work atm , when i get back later on i will send you some info thru.

Regards
Trev

 

[jay]

hi interesting i would tank but if your in doubt set up a sprinkler in shower cube and let it run for a couple of hours and then see were water has gone then when dry waterproof or tank walls and floors let dry and try sprinkler again even with tiles on walls and floor some moisture will get through (grout joints) waterproofing stops it from going further //:8:

 

[heavytrevy]

here ya go
http://www.bsa.qld.gov.au/SiteColle...s/Tech Info/Waterproofing Standard AS3740.pdf

if you still have any questions dont hesistate to PM me.

Regards
Trev

 

[diamondtiling]

Take on board all the comments as they are all relivant experienced opinions.




My answer would be no.......


..

Hi Tony, I don't understand why you would advise not to tank in this situation? Or any wet area? What are the reasons why you advise against it mate?

 

[wetdec]

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.