shower trap - not sure if this seal is correct

[dormermike]

Having discovered that my shower tray was leaking badly i'm resealing it and replacing the trap.

I've got a new trap but can't replace the body which has basically been built into the underside of the shower tray.

Anyway, I bought a 90mm trap, but the opening on the base is 93mm diameter, and the seal that came with the new trap is 85mm inner diameter. Is this expected, or is it all completely wrong? Do i need a 93mm trap? Is the 85mm seal somehow expected to expand to 93mm?

Thanks
Mike

 

[Madrab]

If the seal doesn't fit the grove/ledge of the trap under the tray properly then it might not seal up correctly. Clean and dry and a little silicone both sides might work but no guarantees. The seal should sit nice and evenly and snugly/square onto the trap lip.

 

[dormermike]

Thanks

Ended up having to chip away the (soaked) chipboard which seemed to be bonded to the underside of the shower tray to get the trap to fit properly. The pro who fitted this stuff originally seemingly didn't notice the 5mm gap or maybe they did considering the amount of sealant that had been used.

My leak test (cardboard) seems clear so I think it's ok.

Just trying to dry out six years worth of leak now. It's stinking. Dehumidifier seems to be working.