Confused about wetrooms - TilersForums.com

[Brad]

I am confused about the principle behind tanking a wetroom. In the event of a flood, water will simply find its way through the door to the next room. I don't understand the logic behind tanking a wetroom if this can happen? Tanking is supposed to protect substrates, but adhesive and grout is not waterproof so water ingress will adversely affect the installation whether the room is tanked or not.

Also, as grout is not waterproof, how can it be used with confidence in a wetroom???

Very confused! ........ Some feedback much appreciated......

 

[Dan]

Re: Confused about wetroom tanking

You don't tank a wetroom to protect it against floods. You tank it to protect the substrate during general use.

Water in a shower area for example (one that is using a trap in the floor with tiles around moreso) will mostly fall down the tile and into the drain, but some will work its way through the grout, through the adhesive, and onto the substrate. So you tank the substrate so that water doesn't pass through that part, and runs down into the trap in the floor.

So your tanking should start high up near the shower head, and end in the trap.

Then your tiles are cosmetic and only there for aesthetics and for easy cleaning.

Grout and adhesive should be mainly cement-based in wetrooms which means that no water can damage it per se (it can discolour some grouts but not damage it). Water can pass through it all and not break it down. Though if water soaked into plaster once a day for a few months your plaster could start to deteriorate. And if it soaks into plasterboards that have the weight of tiles on them, expect them all to come crashing down within a year or so. And if you shower naked like I do, that's bad news for the little soldier that now has sharp tiles flying around it!!!!

 

[Ajax123]

Re: Confused about wetroom tanking

Ditto dans answer...

 

[NZ_Tiler]

Re: Confused about wetroom tanking

You shower naked, go figure!

 

[Dan]

Re: Confused about wetroom tanking

Mostly ye.

 

[Ajax123]

Re: Confused about wetroom tanking

Apart from the little flowery shower cap eh

 

[Dan]

Re: Confused about wetroom tanking

Damn it how did you know?!?!?!

 

[Lee garnham]

Re: Confused about wetroom tanking

I agree. My opinion tanking a shower with shower tray is a complete waste of time should large enough quantities of water manage to get past the tiling you got a problem regardless of what water proof product or tanking ect you have used. I tiled the shower in the house I'm in Now when I was an apprentice about 11 years ago straight onto plaster it's still now as solid as the day I put them up. I will always tank a wet room floor or use a similar product in case the water does brake through at some point it should avoid damage to any rooms below.

 

[diamondtiling]

Re: Confused about wetroom tanking

I agree. My opinion tanking a shower with shower tray is a complete waste of time should large enough quantities of water manage to get past the tiling you got a problem regardless of what water proof product or tanking ect you have used. I tiled the shower in the house I'm in Now when I was an apprentice about 11 years ago straight onto plaster it's still now as solid as the day I put them up. I will always tank a wet room floor or use a similar product in case the water does brake through at some point it should avoid damage to any rooms below.

I wouldn't go quite that far? its not a waste of time at all, in fact its a requirement to tank wet areas. If you have installed it correctly using the right trap then the water that may get behind your tiles will work its way down the wall and into the trap.
Mcalpines manufacture specific traps for use with tanking kits in situations like this.

 

[AJPlumbing]

Re: Confused about wetroom tanking

I am confused about the principle behind tanking a wetroom. In the event of a flood, water will simply find its way through the door to the next room. I don't understand the logic behind tanking a wetroom if this can happen? Tanking is supposed to protect substrates, but adhesive and grout is not waterproof so water ingress will adversely affect the installation whether the room is tanked or not. Also, as grout is not waterproof, how can it be used with confidence in a wetroom???Very confused! ........ Some feedback much appreciated......

A properly designed and constructed wet room will have a floor mounted drain, and an fall over the entire floor towards the drain of 1:100 - 1:200 (0.5 - 1.0 cm per metre). Across the doorway should be a 25mm high threshold, also tanked and therefore watertight.Should a pipe in the wetroom burst then these two proven design criteria are sufficient to ensure that no water floods the rest of the building, but instead simply goes down the drain.If a pipe bursts inside a wall then obviously it won't prevent flooding elsewhere in the building.The fall over the entire floor is also a practical measure to prevent pooling of water outside of the shower from general usage. Tanking also protects the substrates from water damage as has been stated by others.

 

[Wheely]

Hi

Tanking is generally to make the walk in shower area waterproof for day to day use, not to retain a flood. In our experience 'wetrooms' are required for ease of access and aesthetic reasons. Adhesive and grout aren't waterproof but are water tight for normal use. Tanking is all about sealing joints and 'backup' for other areas. A wetroom is seen as a luxury over a shower tray, which has its weakest point where sealant is used which as we all know deteriorates over time. Tanking with good tiling/or well fitted vinyl is a better solution than a shower tray.

Neil

 

[bugs183]

As above grout and adhesive are not waterproof, but water resistant, so these will not break down under water. This is why tanking the room to stop any damage to the walls and floors are vital. A flood is exactly what it is, an unexpected event, you could always put an upstand in the doorway if you want to be certain that the water wouldn't get into a nearby room. Image the damage that flood would create in an untanked room.

 

[Brad]

Thanks bugs. It still boggles the mind that we go to all this expense and effort to waterproof a wetroom, and yet in this day and age there is no such thing as waterproof grout, meaning that water can still find its way behind the tile!

I understand that a good addy is water resistant, but surely there is still a risk of the tile dislodging from the substrate if water gets between the substrate and the addy?

 

[AJPlumbing]

Thanks bugs. It still boggles the mind that we go to all this expense and effort to waterproof a wetroom, and yet in this day and age there is no such thing as waterproof grout, meaning that water can still find its way behind the tile! I understand that a good addy is water resistant, but surely there is still a risk of the tile dislodging from the substrate if water gets between the substrate and the addy?

Epoxy resin grout is waterproof.

 

[Brad]

That is true, but it is not flexible and so would not be suitable on, say, a wall with limited movement or a ply floor.