Sink & bath into Soil pipe horizontal

[shergar1983]

Hello, I would appreciate some advice if anyone could spare the time...

I have a soil pipe running horizontally (with correct fall) for 1m before it exits the house. Coming in from the side I have a 40mm which carries the waste from a bath and sink. This needs to connect to the soil pipe.

The 40mm goes through the center(ish) of two joist on its way it and so this cannot be moved. using a flexible compression joint (everything else is solvent weld) it is able to connect to a strap-on boss half-way between the side and the top. The bottom of the 40mm would be inline with the middle side of the soil pipe if that makes sense.

I am concerned because this is happening 30cm downstream from the W/C.

Does anyone know where this leaves us in terms of regs? From what I've read it is on the limit of what is acceptable?

 

[AWheating]

Would drop into soil boxing and connect further down the 110mm pipe.

 

[snowhead]

It's potentially asking for trouble.

Marley recommend a 135 branch for horizontal connections;

Marley Alutec 135degree boss branch 110 x 55mm Grey

 

[shergar1983]

Thanks for both of these. I could go in at 135 however it would just mean that I'd need to add another 135 joint to get it on its way, like with copper I've been trying to avoid these.

This Marley connector, would you fit it with the 135 branch center or alleviated? With the strap-on boss I was intending to have it just above the mid-line.

 

[lucas121]

Do people actually drill 40mm holes in joists? I know regs state it must not be more then a quarter. But I assumed that all waste (other then condensate) through joists was considered a no no.

 

[shergar1983]

Nothing in this house is conventional... The joists are 9" so kind of okay, but I wouldn't have dared. Originally this was done just for a double sink rather than just running outside the wall. I now have the same option after moving the bath to the same location (and just having one sink), however the house is timber-framed with brickwork on the outside. This means I have to bore through the wooden frame, I'm sure this would be okay but I'd prefer not to mess with the vapour seal and generally won't make a hole in anything where there's a way. I'm sure as hell not making more holes in the joists, which would have had this whole drama over with.

Plan is to buy the part snowhead suggested, the angle means it will be about 30cm from the wall and 60cm downstream from the W/C. I can have the bottom of the boss resting at the 3 o'clock position. I will also be fitting an an anti-vac trap to the sink, and an in-line anti-vac for the bath (it's trap is exposed and decorative). Anyone see a problem?

 

[shergar1983]

Just a follow on from the above, I notice the 135 degree connector is female, I plan to just cement a very small pit of 50mm pipe into it before fitting a boss adapter for the 40mm. Feels unconventional though, but can't think of anything better.

 

[joni os]

Welcome to the forum Shergar, 1983 been a long time but we all knew you'd turn up some day. Has Spud Murphy got his clue yet.

 

[shergar1983]

Lol indeed.

 

[snowhead]

Just a follow on from the above, I notice the 135 degree connector is female, I plan to just cement a very small pit of 50mm pipe into it before fitting a boss adapter for the 40mm. Feels unconventional though, but can't think of anything better.

Use a 50 x 40 reducer with 40mm spigot (m-f) bend if you need to get back to 90 degree

40mm Solvent Weld Spigot Bend 135 Degrees W2230 - Drainage Central