Hello,

I am new to the forum and I have no experience whatsover when it comes to installing showers or even tiling so please be gentle with me.

I am paying a company to supply and fully fit a new en-suite in my house. My dad insists that I get the company to tank the shower so I went and spoke to the company but their response was they don't tank showers. The project manager told me there is no need and tiling on green plasterboard will suffice to make it waterproof.

I would greatly appreciate any opinions from you experts and any advice you could offer.

It is good practice to tank a shower area and for most of the guys on this forum I would bet that this would be thier prefference also (some probs woudnt touch a shower without doing it!)

It is however, very common for tilers/ bathroom companies to tile onto areas without tanking. They have at least used green plasterboard. In many cases it is the customer who does not want to pay the additional costs of having the tanking done.

I would suggest you ask the company to tank anyway but you should be happy enough to pay for the time and extra materials to have this done.

Hope this helps

Tanking is a must IMO as it prevents further damage if the tiling fails, which it does occasionally. Cement based grouts are not waterproof and still allow some moisture through to the substrate. Green plasterboard is only moisture resistant and will break down if allowed to stay damp. I always install a membrane for tanking, and for very little cost, gives you greater peace of mind.

Below is a pic of green plasterboard that's been allowed to stay damp for a continued period of time from a leaking shower.

Here is some water damage under the bath which spread across the bathroom floor and damged the ceiling down stairs on a job I refitted.

The benefit of membrane is that the water will not get through. If using tape with liquid tanking kits you can seal over the bath to wall or you can seal full wall and then floor area including intersection where the wall meets the floor giving total peice of mind for years to come. You can also choose sheet membranes.

This picture you see was a job that was probably double sealed e.g. gap of bath and wall was sealed before and after tiling but these seals break down and fail eventualy and permit even more water to enter vulnerable areas. Tanking will prevent damage when your seal fails (seals should be maintained even when area has been tanked)

Tanking is the best way forward if you want to help eliminate chaces of failure

the sooner tanking is incorporated into the building regs the better imo, I hate having to battle with building companies that won't have it installed

If they haven't quoted for it,you won't get it unless you pay extra.Do you have any thing on paper to say the work will last? Are they a national company or local builders that do tiling.

Thanks for those great responses, I've now decided that I'm not going to allow the installers to install the shower without tanking. Paying for the extra materials and time does not bother me in the slightest, I get the impression it's more a case of the installers can't be bothered doing it. I'm paying this company £6k for this job!

Good choice

well done better safe than sorry , dont let them talk you out of it either

Originally Posted by Del W

If they haven't quoted for it,you won't get it unless you pay extra.Do you have any thing on paper to say the work will last? Are they a national company or local builders that do tiling.

I will have to go back and speak with them further, I am willing to pay the extra costs. The en-suite is directly above my living room, I don't want water leaking down into my living room in a couple of years time. This company sells bathroom furniture and tehy have their own tradesmen that do all the installs.

If they won't do it willing you could always go in there and do it yourself. A lot like painting a wall. Liquid ones generally require two thin coats with the taping membrane going into the internal angles. There are plenty of instructional videos on you tube

The BAL WP1 Waterproof Kit looks ideal for my needs, would you agree? It's only £50. How much extra time would it take the installers to apply it?

they would need to tank it and then come back at another day

They could tank that area, and continue to set out and possibly start tiling the rest of the room. Doesn't mean they'll always have to loose time on the job waiting for it to dry.

good point, they may be able to crack on with some of the other work needing done

Pleased to see you are doing as your Dad suggested.
With the Homelux tanking kit at the price you quoted it should cover about 5sq mts and should take about 1 and no more than 2 hours to install.
It is fixed using the same waterproof adhesive as the tiles and if they use a fast set flexible cement based adhesive they should be able to tile on it within 2 hours from being fixed.
Check the tile size/weight issues for your walls and also the background preparation/substrate - if they are reluctant to tank they may well be reluctant to prepare correctly.

Also check out Mapei's NEW!! tanking system.. Aqua defence and this is rapid drying..

For £6k they should be tanking it as a matter of course! The green boards may well be water resistane but not on the joins and where it meets the bath or tray.