waterproofing showers

Hi, Very Happy Christmas. I'm an old lady and haven't fixed a shower before so please be patient. I have spent 6 hours on the computer tonight researching and trying to decide what to do next. I have had a workman in to put in a new shower for the last two days. It is costing £2,000 (this doesn't include cost of electric shower or shower door - using existing) so I want to make sure it will not leak. I got suspicious after the second day. Day 1 the existing shower taken out. Day 2 the area was plastered. Day 3 the guy proposed tiling, but the plaster was still wet and I protested. He has left it to dry out until monday (this will be a week) and is coming back to tile then. My worry is that there is a gap of nearly three quarters of an inch between shower tray and wall. I will of course ask how he proposes to fill it, but if with silicone only I'm pretty sure this will not do. I'm wondering about paying him for work done so far and tanking/tiling myself. I have done some tiling in the past. I was thinking of doing the following and would be grateful for any advice, both about whether I am being unfair to the workman, but also about my ideas for waterproofing. Here's my plan.
1. Wait 4 weeks for plaster to dry completely
2. Fill gap with lots of silicone
3. cover gap with sealux
4. Apply BAL tanking system.
4. Tile and group with waterproof adhesive and grout.

Even sober this post seems a tad strange to me, but here you go.
I am not a tiler/plasterer by the way.
Just a few questions which give us more information.

Is one person over-seeing the entire job ? Have you spoken to them about the concerns you have, as they arise ?

Have you paid any money for the work ?.

Happy with the original quote ?

Do you really feel capable of doing the job ?

Happy-X-Mas anyhow.

Ed

Hi Ed, thank you so much for getting back to me on Christmas Day. Why does the post seem strange? One guy is doing the work and overseeing it. The original quote was for 1300 for labour only (I have bought all the bits an pieces and spent an extra 650 so far). Yes I was happy with the original quote but I thought it was a bit expensive for the basic work which was essentially taking out the old tiles and tray and replacing them/tiling and replacing original door. I asked him to replace the sink too, AFTER the original quote and we didn't properly agree a price, but he said extra £100 which is fine, but it's a mess and I'll have to have it taken out. I used the spirit level today and see the plastered wall is concave which is why there is such a big gap in the middle between shower tray and wall, also notice the plastering at the base of the wall where it meets the tray is a mess - quite a few holes, also the door is 800 mm and the space is 815 mm - so worried about door fitting and think plaster layer might be slightly thinner than previously. Wondering now if the tray needs to come out altogether (cemented in somehow) and wall need more plastering. You can see I'm now obsessed and it's Christmas day - can't do any cooking - kitchen off shower and full of plastering stuff and equipment. I could do the tanking myself with all help on internet, and pretty sure could do ok job of tiling. No way could do plastering. And couldn't take off sink again and replace or put on shower door. Thinking do what I can, and find someone else to help me with jobs I can't do. I have paid £700 cash so far. Sorry this is so long. Hopefully you won't be reading it again on Christmas Day!

A lot of questions here, but to the original how to fill the gap, I should use expanding foam (trim excess when dry). It will get down into the gap to make a good seal, it sticks to just about everything and it's waterproof. I don't know what the wall is made of nor what the shape of the shower tray is, but you should be able to make a good deep seal.

Hi Kes, thank you very much for your reply. I was wondering whether expanding foam would be better than silicone. I will use it. I hope you are having a good Christmas. Any thoughts on what to do about the bad plastering down in the corner - not a good surface for tiling on. Could I just try and use a filer and then sand before I tank? (the shower base is fitted in now)

Kes said:

A lot of questions here, but to the original how to fill the gap, I should use expanding foam (trim excess when dry). It will get down into the gap to make a good seal, it sticks to just about everything and it's waterproof. I don't know what the wall is made of nor what the shape of the shower tray is, but you should be able to make a good deep seal.

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Expanding foam is not longer waterproof after you have cut it if the cut face is exposed .

confused again - silicone or expanding foam for filling big gap before tanking shower? any other thoughts?

Get the geezer to sort it out - you're paying out a lot of money and you want it perfect without you having to lift a finger.

you say your ok with tiling, but wouldnt do the plastering?



i have to agree with GC here, talk to original guy if then your not 100% happy, get someone else in.

many thanks for all responses - especially over Christmas. I am very grateful and getting clearer. bw Susan

You can get a system called bal wp1 its a tanking system designed purposly for showers its simple to use it literately paints on and everything you need comes in the box...... No one should use plasterboard as a backing to tiles in a shower as it will fail as grout isnt water proof its just water resistant (unless its epoxy) Id insist on this at least other wise its only a matter of time till it all needs doing again . hope this helps and its not to late..................

Many thanks. Have tanked using Sealux and BAL WP1 already - easy to apply and good stuff. Just hoping the tiles stick and look ok. The walls have not been plastered straight and there's quite a bump between sealux, BAL tape and wall if you see what I mean. If they'd been plastered straight it would all be brilliant. best wishes,

kim119 said:

No one should use plasterboard as a backing to tiles in a shower as it will fail as grout isnt water proof its just water resistant (unless its epoxy) Id insist on this at least other wise its only a matter of time till it all needs doing again . hope this helps and its not to late..................

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I don’t disagree with your sentiments but just to nit pick a little; ordinary PB & even moisture resistant will eventually disintegrate if they get wet but “tanking” as you suggest & as “headwrap” has used, is a perfectly acceptable method of treating them & will work if it’s properly applied. If starting from scratch, however, I always prefer to use a waterproof backer board.

Waterproof adhesive/grout IS waterproof in the sense that it won’t disintegrate when wet but it’s not impervious to water & it’s the water permeating through that causes the PB underneath to disintegrate. Epoxy adhesive/grout is impervious but rather expensive!

Well now richard you seem to know your stuff, and I do agree with you wedi or systems like that are the best solution obviously but again alot more expensive than plaster board and if your a dodgy builder cost (or should i say profit) is the most important factor. If only there were more people like you out there , then there would be no need for these sites and people would get jobs done the way they should be............

Hi, am following this discussion with interest - now too late for me, but the builder (I asked him to p... off by the way) used plaster not plasterboard or waterproof board of any kind. What are your thoughts on using finishing plaster beneath the BAL WP1? My main concern is that it is not flat and therefore the sealux and tape didn't have an adequate surface area to adhere to in some places - and therefore nor while the tiles - which by the way i haven't dared start on yet. best wishes.