Alternative to Aquapanel for shower construction - long winded post!

[TandC]

I can't tell you how bored I am with my shower.... i want to get it resolved and it to never ever leak again.....!

 

Original design, I used a universal shower tray - a white plastic job which has an extra wide flange around the shower well which allows it to be cut to the perfect size. This is necessary as I cannot move the walls.

 

Once trimmed to the perfect rectangle, the tray flange butts up exactly to the walls so that works fine, allowing the largest possible shower area. It stands on a wooden support all around the sides and under the well to prevent any flexing of the plastic.

 

The problem is that as a result of the trimming, there is no integral, molded upstand to the shower tray edges, so any fail in the seal can run out.

 

When fitting it originally, to tackle that risk I siliconed some 90degree plastic trim around the edges to provide an upstand.

 

The PVC cladding is then simply cut to size and siliconed to the walls, cut so that it sits over the top of of the upstands as described above and with a sealant again to the showertray. I've never had a leak through the PVC cladding or the corner joints.

 

This double-seal at the shower tray edge has inevitably failed after 5 years. The water has ingressed through the join of the cladding/showertray, and then eventually the 90degree trim has lifted from the back edge of the tray and water has been able to run out, all over the walls and into the bilge. Triffic!

 

Soooo.... two issues - sort out a more solid and permanent upstand to the shower tray - because I have to use the same one in order to fit the space (i have a brand new replacement, same size, but same design).

 

Secondly, I need to fix the new PVC wall cladding to the walls, over the upstand and seal to the shower tray.

 

Upstands: I thought about Aryldite gluing 90angle plastic to the showertray so as to guarentee a watertight bond that will never fail.

 

I've also considered using fibreglass/polyster resin/glass tape to create a larger 90 degree upstand - bonding it from the underside of the tray and around a former to create an upstand of an inch or two high, which I am even considering then bonding to the walls for 100% fix. - albeit that means if the shower tray has to come out for any reason, that its going to be glued to the walls which isnt ideal.

 

And then to fix the PVC cladding to the walls - last time I must have just used silicone adhesive squirted all over the walls and the panels just pushed on and 'glued'. I need the cladding to be really rock solid fixed to the walls - i dont want any flex causing the sealant to peel away. Just to make things more difficult, the back wall has a load of old tile grout all over it. It's relatively even, but could mean that the cladding is able to flex slightly due to high/low points....

 

What is the best adhesive for the PVC cladding to plywood - I was thinking about maybe something like GripFill or PinkFill - a proper hardcore grab adhesive? I was thinking of using wood cut to length to 'prop' or jam it into place all over, pushing the cladding against the walls while the adhesive goes off.

 

Finally, Aquapanel has been suggested as a medium to cover over the plywood and grout to provide a solid and smooth substrate to PVC clad to. But i just cannot lose that much space (its 12.5mm thick so that is 2.5cm from the width and 1.25cm from the back lost in shower size - you already need to be a midget, plus it would mean the shower tray won't work any longer....). Is there anything any thinner??

 

Sorry for the length of this post, but this shower is probably the best example of having to deal with a terrible job done in the first place!!

 

 

 

 

[OldGoldy]

 

What is the best adhesive for the PVC cladding to plywood - I was thinking about maybe something like GripFill or PinkFill - a proper hardcore grab adhesive? I was thinking of using wood cut to length to 'prop' or jam it into place all over, pushing the cladding against the walls while the adhesive goes off.

 

 

Not a job I've had to do, but would have thought silicone(?) sealant for the PVC cladding and a flexible polyurethane adhesive/sealant such as Sikaflex/Marineflex/Tigerseal etc for the shower tray/upstand.

[TandC]

Ahh ha! Further research shows that there are 6mm backer boards available, specifically for tiling onto..... I don't want to tile onto it, but the benefit of this stuff is that it is supposed to be stable in damp conditions and would provide a solid substrate to glue the cladding too, smoothing out the bumps of the old grout. I could just about get away with losing 6mm from the back wall....

 

http://www.toppstiles.co.uk/tprod3919/Hardiebacker-250-Cement-Board-6mm.html

 

Does this stuff just snap though if screwed against a wall where there is an obvious high point, or does it have any degree of flexibility?

 

 

Thanks for the reply OldGoldy - in just not sure that silicone is man enough, it seems to fail after a few years. Is the MarineFlex silicone sealant also mould resistant? As that is another problem....

Edited September 25, 2013 by TandC

[The Bagdad Boatman (waits)]

B&Q used to sell clip together panels which I have used maybe 8 ft by 2 ft. 5 to 10mil thick hollow plastic. Slit the back to curve the corners. not very flash colours, Bath edge strip come with a rubber seal and an upstand to fit behind the shower wall. Wicks have this which looks the same. http://www.wickes.co.uk/invt/162657

[TandC]

Thanks BB.

 

The PVC cladding is all sorted - I used clip together stuff last time which was fine - looks good, cleans well etc - only issue is the lines between panels inevitably allow a place for mould. This time I have splashed out (groan...) and bought the full size panels 1m x 2,4m which mean no joins other than in the corners.

 

If there is a good bath edging strip that works with this stuff then that I should research more....

[bottle]

Whatever sealant you use will fail after time, it will come down to monitoring and preventive maintenance.

 

Boats always flex especially when the sun iis on one side for example.

 

Now if you can find a way for the cubicle to 'float' within the boat that may reduce the the failure rate but not forever.

[smileypete]

A well designed and made 'expansion joint' shouldn't fail.

 

I'd consider fixing the 'L' shaped plastic to the wall instead so the lip is 1/4" to 3/8" above the tray, then fill to 1/4" depth using something like a slice of grey foam pipe insulation as a 'backer rod'.

 

BTW Dow 785 is good sealant, Screwfix have it.

 

cheers, Pete.

~smpt~

[TandC]

Thanks Pete - I' ordered a few tubes of that only yesterday so that's reassuring.

 

I've decided to cut out the piece of ply lining which is covered in tile grout as there's just no way I can fix anything over the top which is going to be level. There are so many ridges that i'm pretty sure Aquapanel will just snap if fixed with any firmness. I'm going to cut out the ply using one of those multi-tool saws and refix a new section to the battens behind, giving me a smooth surface to work off.

 

I'm not sure I really understand the expansion joint - isnt the point of an permanent upstand at 90degress on the edge of the showertray to prevent water running out?

[smileypete]

Well unless the shower tray and wall are absolutely rock solid there's always going to be some movement between them.

 

So if some plastic trim is stuck to both sides with a sparing layer of sealant it'll pull off eventually, there needs to be a thicker seam of sealant somewhere to take up the movement.

 

Bit like a traditional wood deck on a boat, the wide seams of sealant aren't to make it look pretty, but take up movement from the wood planking as it often gets damp and dries out in all weathers. If such a deck done properly can last 10-15 years I'm sure a shower indoors can't be impossible to do

 

If you draw a cross section diagram with some dimensions that might help, maybe also post it up so others can take a look.

 

cheers, Pete.

~smpt~

Edited September 29, 2013 by smileypete

[TandC]

Well, progress was slow, but has been made of sorts....

 

I bought one of Screwfix's £30 multi-tool saws and using the cranked blade was going to cut out the wall linings which were covered in old tile grout - but I found that if used to cut up behind the old grout, the heat of the blade friction actually partially melted the old grout and it peeled away - it took a few hours but it meant that I cleaned off all the old grout leaving a much much smoother ply substrate onto which the PVC cladding can be glued, so that has helped already in preventing any flex in the shower walls. I am not going to use Aquapanel any more as I would lose too much space if i did all the walls, and to be honest, there wasn't a hint of moisture on them before so I think the PVC cladding has been working well, its just the seal at the bottom that needs to be cracked.

 

Ive built a much more substantial wooden platform and frame into which the showertray fits with almost all horizontal surface, particularly the 'flange' and where it meets the wall, firmly supported. As a result there is now no movement in the showertray.

 

It maybe a bit drastic, but I've then used fibre glass/epoxy to seal all around the edge, joining the showertray flange to the wall permanently. This has hopefully created a permanent watertight bond between showertray and walls in case the silicone sealant fails. I can still access the plumbing fittings from underneath.

 

The next stage is to install 'Cladseal' - this sits over the top of the join between shower tray and wall - thereby hiding the fibreglassing, - it is a pvc trim which is screwed to the walls and a deep bead of (good quality Dow Corning) silicone inside the trim is used to bond it to the shower tray - enough that it will be flexible. http://www.pvc-cladding.com/proddetail.php?prod=Clad_Seal shows what it does. I think the benefit is that as the sealant is INSIDE the plastic trim, it means that it doesnt sit in the wet, preventing it going mouldy. I may be wrong on that one.

 

I could add a final very thin bead of silicone on top of the cladseal, and this can be the 'sacrificial' layer - able to be removed every few years and re applied.

 

The PVC cladding is then cut and fitted over the top of the cladseal trim.

 

I am hoping that this will work, and that it will also provide a far easier way of carrying out maintenance in the future. Time will tell....