Sealing drain inside bathroom

[Rimrogs]

I have 2 open 4" (ceramic/porcelain type) drains in my bathroom - one for the toilet & one for the shower/basin. The toilet drain is straight forward - I'm concerned about the other one.
How can I seal it after directing 2 std 32mm plastic pipes into it? It will eventually end up under a shower tray. I believe it isn't the u-bend sort as I can feel air blowing through it.

 

[jobloggs]

Do these end in a socket at or above floor level? I assume it is a solid floor?
l_ _l
l l

If so you could possibly cut a piece of thin plastic sheet or thin metal sheet to fit the bottom of the socket with cut holes in this for your pipes. Seat this into the bottom of the socket with silicone and seal round pipe openings. How is the waste from basin and shower being positioned under tray?

 

[Rimrogs]

Hi Jobloggs
They resemble the first of your sketches reducing to about 75mm about 50mm down (does this grammar make sense?). The top of the pipe is almost flush with the concrete floor - approx 12mm below the surface.
I see what you mean - the plastic will sit in the recess?
I've built a 100mm square frame on which to sit the shower tray. This gives the height to allow the waste pipe to be threaded through as the bottom of the tray is also at floor level.

 

[Rimrogs]

Hi Jobloggs
They resemble the first of your sketches reducing to about 75mm about 50mm down (does this grammar make sense?). The top of the pipe is almost flush with the concrete floor - approx 12mm below the surface.
I see what you mean - the plastic will sit in the recess?
I've built a 100mm square frame on which to sit the shower tray. This gives the height to allow the waste pipe to be threaded through as the bottom of the tray is also at floor level.

 

[jobloggs]

It was all one sketch but didn't appear as I had done it.

Yep plate with holes seated in bottom of recess.

 

[kevplumb]

use an anti syphon trap as well