I am currently rebuilding from a disasterous shower failure that rotted the
entire bathroom subfloor. It was a fully tiled shower stall with durock
backer and PVC floor membrane. It was done by a contractor and I found a
razorblade cut in the membrane probably made while cutting the drain and
few other violations of the proceedures I've been reading on various info
sites. The original shower had failed in less than 10 years and the rebuilt
one destroyed the bathroom floor in five years.
The shower walls are still good with tile over durock and I would like to
keep them if possible and replace only the floor. I cut out the damaged PVC
membrane which extended behind the backer. I can't get a new one behind
there without tearing out the walls. I don't want another tile floor anyway
for this basic reason:
You are depending on a moisture barrier which you cannot see hidden below
the tile. If it fails, you don't know until your subfloor starts to cave
in. Now I want to install a moulded plastic shower base so that the
moisture barrier is the surface I'm standing on so if it fails I will see
My problem is joining the top flange of the shower base with the tile walls
in a way that won't leak. I have read how this is done if you are building
the walls from scratch over the base, but I want to keep my walls. The base
is not a perfect fit. This is more of a problem than I thought it would be.
I'm now considering custom building a base in-place with glass/epoxy (I'm a
boatbuilder). I'm starting to think it might be easier to tear down the
walls and start from scratch.
I would appreciate any advise.