Hi Folks, We have a shower cubicle of a non-standard size, with block walls on three sides. I got a custom shower tray made from stainless = steel for the base of this shower, with a lip on it of about one inch. I tiled th= e walls of the shower and rested the bottom row of tiles on to the stainless steel = base, so that shower water would fall into the base and drain away nicely: no wor= ries about the integrity of the join twixt tiles and base here. I then bought the good silicone stuff (can't remember the brand name, but e= ach cartridge was =A37.50 a time all those years ago) and the shower has done w= ell for a few years.
The problem started about a year ago: the other side of one of the shower c= ubicle walls is wallpapered, and the black bacterium started to flare in spots fro= m the base up to about eighteen inches off the floor. The other wall is in an adjoining room, and it too showed the same symptoms. The tiles used are those flaming difficult ones to drill, and are about fou= rteen inches tall by about ten wide.
I cursed my luck and decided to remove the bottom row of tiles, and the pla= ster work behind them was damp. The plaster at the very foot of the tiles for up= to about a half inch was sufficiently wet that you could "rub" it through your= fingers. Bug*er.
Its dried out for about three weeks now, hence I'm getting pestered to get = the shower fixed (we have two other showers in the house, so no catty comments = about personal stench please :-) . But how to fix this: if I do what I did last time, the problem could come b= ack. My guess is that the water was somehow "wick"ing up the back of the tile an= d up into the wall.
Current thoughts are to buy some of that plastic "quadrant" tile edging stu= ff (not the kind that is used to tile down to the top lip of a bath), and use this = to keep the bottom edge of the tile off the stainless steel. I'd also make sure that the bottom two inches of the wall are painted with = gloss paint so that any water on its surface wouldn't seep in and work its way th= rough.
I'm using one of those two-pronged damp meter things; it's not exact scienc= e but its quite useful. The numbers have dropped since the shower was decommissioned, but I guess that's to be expected.
Grateful if anyone has views on this; many thanks in advance.
Mungo