Shower connection to 110mm waste

[Wavy Davy]

Hello,
New shower install. I want to connect 40mm shower waste to existing 110mm waste coming up vertically through concrete floor. 110 mm has socket end projecting 50mm above floor. What's my best option?

1. Cut socket flush to floor and join in with an adapter?

OR 2. leave as is but have to raise shower tray higher.

Thanks

 

[Madrab]

What else, if anything is the stub to be used for? Is there anything else being connected to the shower waste run? If nothing else then could use a strap on boss and cap the pipe, or cut the pipe down and insert an adapter cap as mentioned. How is it to be enclosed?
How long is the waste run to be? If it's a low profile tray then get as much fall on the waste run as possible to encourage good flow and self cleaning (as close to 45mm/m as it can be)

 

[Wavy Davy]

Thanks Madrab,

Stub is only for shower, nothing else will be connected. Stub will be underneath tray offset from centre of tray. So waste run is short.

I favour cutting flush & using adaptor. If that's OK, how best to do this? How do I fit adaptor if they are made for 110 mm dia but remains of the cut socket will be slightly wider?

I was thinking of fixing a short length of pipe into socket with a good sealant and then pushing adaptor into it.

Is that acceptable?

 

[Madrab]

Yes - you could just cut the 110mm pipe to ground level then just insert one of these - 110mm to 40mm reducer

 

[jamiesun]

Cutting flush and using an adaptor is a solid approach, but you’re right to consider the issue of the remaining socket being slightly wider after cutting.

A few ways to handle this is:
Cut carefully – Use a multi-tool or fine-tooth saw to get as clean a cut as possible.
Deburr & smooth the edges – Sand or file down any rough spots so you get a snug fit.
Use a short length of pipe – As you mentioned, fit a short piece of 110mm pipe into the remaining socket using solvent weld for a strong seal (or a good quality sealant if solvent weld isn't an option).
Fit your reducer/adaptor – Once the short pipe is in place, you can then fit a 110mm to 40mm reducer inside it as normal.

 

[Wavy Davy]

Lovely. Thanks guys!

 

[trojanhawrs]

You also get offset ones like these which might give you a bit more fall if required

 

[Wavy Davy]

Thanks for that