"Sanitary" mastic - second attempt

[clive.r.long]

In a moment of madness I had "stone tiles" put on the floor and walls of th e 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 s hower (it's all covered in tiles, no plastic tray) causing a hard to diagno se 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?) t hat has good adhesion to stone tiles? Should I prep the area where I am goi ng 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 t here is a hint of mould on the mastic?

Thanks,

Clive

[John Rumm]

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

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.

[tabbypurr]

the bathroom.The shower tray is a pre-formed composite material that is til ed. 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 diag nose 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?) that has good adhesion to stone tiles? Should I prep the area where I am g oing 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?

Bleach doesn't affect silicone IME. I assume you're using silicone not acry lic.

Probably the most common cause of silicone failure is expecting it to stret ch. It can only move a small percentage of it's own size, and that often co mes out to well under 1mm in practical applications. Overstretch it as thin gs move and it fails. Do degrease before applying it, muck is the other cau se of failure.

The most common cause of acrylic failure is using it. Only optimists think it suitable for bathrooms.

NT

[nothanks]

In a similar situation I used a plastic (ceramic lookalike) quadrant and bedded it in silicone - it was still fine when I moved house 10+ years later. I will be doing the same when I get around to the bathrooms in the "new" house.

[Dave Plowman (News)]

The normal sealant to use here would be silicone. Anything which peels off easily either is poor quality or not correctly applied. Since it is a form of glue, surfaces have to be clean.

I'm assuming there is no obvious movement between the two?