Our shower trap is leaking and I am trying to repair/replace it. It all seems very straight-forward except for the question of how to seal between the threaded waste flange and the opening in the shower tray.
I bought a new trap, whose instructions say to use silicone sealant between the flange and the shower tray, but the sales guys where I bought it said that no silicone sealant is needed. I fitted it dry and it didn't leak when I poured a bucket of water into the tray but did leak the next time someone had a shower.
I am wary of using silicone sealant, as the motion of threading the flange into the trap will move the sealant and perhaps leave gaps. If it continues to leak once the sealant is dry then the only way to remove the flange to try again will be to cut it out, which won't be easy.
The original flange had just a thin washer between it and the shower tray, but I haven't been able to find a new version of this washer (it feels like a form of soft polystyrene). I'm not even sure that a washer alone is adequate - the plumber that fitted it was incompetent (e.g. he fitted the shower enclosure without mastic between the back of frame and the tiles so it leaked the first time we used it) so I have no faith in how he chose to seal it. Also, we don't know how long it has actually been leaking (the shower is in place for a few years, but only recently did enough water build up for it to soak through the ceiling below) so it is not clear whether the washer ever provided a watertight seal.
So, is the best way to seal between flange and shower tray to use appropriate silicone sealant, or to use an appropriate washer? Thanks for any advice.
I bought a new trap, whose instructions say to use silicone sealant between the flange and the shower tray, but the sales guys where I bought it said that no silicone sealant is needed. I fitted it dry and it didn't leak when I poured a bucket of water into the tray but did leak the next time someone had a shower.
I am wary of using silicone sealant, as the motion of threading the flange into the trap will move the sealant and perhaps leave gaps. If it continues to leak once the sealant is dry then the only way to remove the flange to try again will be to cut it out, which won't be easy.
The original flange had just a thin washer between it and the shower tray, but I haven't been able to find a new version of this washer (it feels like a form of soft polystyrene). I'm not even sure that a washer alone is adequate - the plumber that fitted it was incompetent (e.g. he fitted the shower enclosure without mastic between the back of frame and the tiles so it leaked the first time we used it) so I have no faith in how he chose to seal it. Also, we don't know how long it has actually been leaking (the shower is in place for a few years, but only recently did enough water build up for it to soak through the ceiling below) so it is not clear whether the washer ever provided a watertight seal.
So, is the best way to seal between flange and shower tray to use appropriate silicone sealant, or to use an appropriate washer? Thanks for any advice.