Bathroom refurb. Shower tanking

[FlatcapPirate]

Hello everyone! 

 

First time posting, although I have been reading the wealth of knowledge on this forum for some time. 

 

We are mid bathroom refit. New toilet, wash basin, washing machine and calorifier have been fitted / plumbed. And a whale gulper has gone in. 

 

Now the shower, we hoped it would be simple, alas the previous owners tiled straight onto the ply with no sealant onto the substrate. Also with standard tile adhesive not silicon, so it has cracked and leaked very badly onto the panels behind.

 

We have a new stone resin tray and PVC shower walls ready to fit. My plan was to properly tank the bathroom with a Mapei Waterproofing kit before fitting these, although not entirely necessary. 

 

But now we need to deal with the state of the wood. How bad does it actually look? - I am no wood expert

 

What's the best approach? Let it dry out and treat with some type of wood preserver? Rip it all out and start again (not a huge fan of this as it will delay things massively. The rear wall is the bulkhead into the kitchen / oven splashback) 

 

I was ready to sand it all off and start tanking tommorow and then to panel the next day. Should we hold off from this plan? 

 

Thank you! 

 

Edited December 7, 2020 by FlatcapPirate

[Richard T]

Welcome to the forum.

 

To do the job properly its got to come out. You could take out all but the bulkhead to the galley and fit a cementitious board - Hardibacker or similar - to all areas and accept that the gally area is manky and might fall apart at sometime in the future!! It is possible that wet rot will develop unless you thoroughly dry any damp areas. Another thought is that you cut out the really bad areas and fit new ply. I would then overboard everything rather than attempt to sand off the old tile adhesive - any bumps left will grin through your PVC lining. You will need to fill and sand back where you fix the overboarding.

Edited December 7, 2020 by Richard T

[luggsy]

You could use wood hardener on the wet bits

[blackrose]

I used some Hardibacker cement board behind my shower panels. It's good stuff. In not sure about the state of your ply walls. If they're not completely rotten and they're fully dried out then I'd be tempted just to put the cement board over the top. Screw it on and then stick your shower panels on with Stixall. I used a product called Showerwall as a replacement for some tile effect PVC panels which cracked along the "grout lines"  and leaked! Showerwall is expensive but use a decent panel. Cheap stuff just isn't worth it.

[Murflynn]

if you have any pride in your work and in your boat, in years to come you will always have a nagging doubt in the back of your mind about that rotten plywood and a vision of fungus growing in the dark un-ventilated parts of the boat.

 

Sorry, buddy, but it has to come out.

[Onewheeler]

If any rotten bits are local and superficial, I'd be inclined to hack them back to solid wood with a chisel, apply preservative and cover with 6mm ply (or something of your choice).

[Old Son]

I would also remove all of the wet and rotted ply. It's too much work to have to do it all again and there is not an easy fix if mould starts to smell from behind. Much simpler to do it now.

[FlatcapPirate]

Thanks for the advice everyone. 

 

I have decided that it's best doing right, once. I don't think I could stand the idea of patching it over only to discover problems further down the line. 

 

We have taken out the side panels and removed part of the galley, so we can get the bulkhead out tommorow. 

 

The bottom edge is totally crumbling to touch, so the right call. As it turns out the chipboard of some of the kitchen units is weetabix as well. That's the pushed forwards the galley upgrade project then... 

 

Onwards!