Why Tank

[potatoman]

Hi
If you tile onto a plasterd block wall for a shower do I need to tank the wall ,if so why

Thanks in advance

[blocko]

Water will soon find its way into and through the plaster, causing it to "blow" and leach through to the other side of the wall. I will attach some photos of a plastered wall next to an untanked shower in a few minutes........ I show this to all of my clients. It is the reason I insist all shower areas are tanked

[potatoman]

Would BAL WPI Tanking Coating do the trick

[blocko]

Here you go mate.......
....and yes the Bal kit will be fine ( a bit expensive....may want to try Mapei Shower waterproofing kit )

[whitebeam]

Here you go mate.......
....and yes the Bal kit will be fine ( a bit expensive....may want to try Mapei Shower waterproofing kit )

That must have been soaked on the tiled side.

[blocko]

That must have been soaked on the tiled side.

Yes, this was in a small local business changing room (the wall on the other side of 2 power showers). The showers were used around 3-4 times a day for 10 years. Wall is solid block (plastered) and was growing all sorts of different mould. Wall was like a sponge. Very nasty indeed!

[Scott]

You dont HAVE to tank but it is advisable. The water 'can' get into the wall, its not a given that it will. I have removed plenty of old showers that had some pretty rough tiling and grouting that had no evidence of ever being damp let alone wet.

However for the cost and the time i tank all my wet areas.

[blocko]

You dont HAVE to tank but it is advisable. The water 'can' get into the wall, its not a given that it will. I have removed plenty of old showers that had some pretty rough tiling and grouting that had no evidence of ever being damp let alone wet.

However for the cost and the time i tank all my wet areas.

You are right Scott......... I think it should be British Standards myself

[Mike]

the worse one i seen was when i ripped my brothers shower out and there was all sorts growing there, i was nearly sick. i always insist on tanking now

[Stewart]

This is a job I'm doing this week, which is a total rip-out due to a leaking shower that wasn't tanked.


I always insist on tanking a shower...!

[blocko]

Nearly identical to the job Im on at the mo!........At my job the water damage has spread under (and through) an adjoining stud wall and into the floor in next room (bedroom). I have just finished ripping up 30 sqm t&g flooring, skirting, plasterboard etc etc. If only it was tanked! Keeps me in a job though

[whitebeam]

I wish I had a camera with me when I had to regrout on a job, tile pushed through the plasterboard, most of the timber stud work had disappeared.

[lucius]

So water must pass through the tile or more likely the grout,or bad workmanship or wrong materials to cause this kind of failure so all tanking will do in this case is trap the water between tiling and tanking and eventualy blow tiles of wall but the tanking will prevent anymore water damage. In my lifetime ive seen loads of showers tiled on plasterboard with no tanking but the correct mats used with no problems so i have my reservations about using expensive tanking systems when with using the correct materials realy not needed, just my opinion though.

[Scott]

It can be down to materials and it only takes that one pin hole in the grout for it to get in and fail, so yes sometimes its down to poor workmanship.

[Mike]

normal grout is not waterproof. after soaking water/dampness can get through the grout but if its tanked and bagged adhesive used no damage will be done to the substrate and the tiles won't lift.

[lucius]

In that situation then where would the water go the, its trapped.

[Stewart]

In that situation then where would the water go the, its trapped.

The moister that gets into the grout will come back the same way when the shower isn't being used.

[Barry bp]

I tank when i feel necessary but not often i feel using good quality products and good workmanship is most important if tiling is failing tanking prevents further damage but you still have a problem imo i dont believe water should be getting to background.

[Rich]

I always tank when given a choice for the reasons above.

HOWEVER, I bet 99% of the time it is bad workmanship that causes these wet areas to fail, I can usually tell a customer what has happened before I even look at the job. The "tiler" hasnt used silicone in the internal joints or the "tiler" has siliconed over grout in the internal joints. If proper movement joints/grouting was always used then there would be no need for tanking.

But as said above, for the very small cost of a tanking kit, tank all wet areas and THEN use the right materials and very importantly movement joints.

Thats my take on it anyway

[Stewart]

The sooner it becomes the industry standard to tank all showers the better.......

[whitebeam]

I'm surprised insurance companys hav'nt latched onto tanking, the amount of claims for damage to propertys from leaking showers.

[Rich]

I'm surprised insurance companys hav'nt latched onto tanking, the amount of claims for damage to propertys from leaking showers.

Thats a good point mark, I hadnt thought of that. Must cost them a fortune.

Im going to put up a post about my girl friends mother's shower room that she has just had repaired. Should make you laugh.

[Barry bp]

Movement is one of the biggest probs thats why i build the showers i tile

[Stewart]

Report I did for an insurance claim a couple of weeks ago came back with a note saying the tanking part was an unnecessary part and would not be paid for.......