On 03/01/2018 20:12, wrote:

In a moment of madness I had "stone tiles" put on the floor and walls
of the bathroom.The shower tray is a pre-formed composite material
that is tiled. The mastic pealed around the junction between the wall
and floor of the shower (it's all covered in tiles, no plastic tray)
causing a hard to diagnose water leak. When pulled, the mastic pealed
off the tiles like opening a new zip. Is there a good "sanitary"
sealant (what does that mean anyway?)

It means it contains a fungicide to attempt to prevent mould growth in
wet and humid environments.

that has good adhesion to stone
tiles? Should I prep the area where I am going to reapply mastic in
any way apart from leaving it all to dry out for a couple of weeks?
Does dilute bleach cause mastic to fail which I use when there is a
hint of mould on the mastic?

Try one of the Modified Silane (MS) sealant / adhesive products. They
tend to have more adhesion to stone surfaces. They are a little
"stiffer" to work and shape, and are not quite as glossy once set.


--
Cheers,

John.

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