Belfast sink - joining old waste to new 40mm trap and pipe

[JimCrow]

This will replace your existing 1¼" McAlpine bend on your pan connector to take you to 1½" waste pipe.
https://www.wolseley.co.uk/product/mcalpine-t5m-a-95deg-bend-multifit-x-bsp-nut-15/

 

[Madrab]

Be aware that those pan connectors aren't really supposed to be for plumbing in basins, of course some 'plumbers' use it for that.. That's really to allow a vent to be fitted if there's an overly long soil pipe run etc.

 

[DIYNotIan]

Be aware that those pan connectors aren't really supposed to be for plumbing in basins, of course some 'plumbers' use it for that.. That's really to allow a vent to be fitted if there's an overly long soil pipe run etc.

Thanks Madrab. I didn't realise that at all. I'm guessing it's been like that since the extension was built 20 years ago. Whilst not "proper" are there any practical problems having that set up? I've got the impression it might be quite a popular "bodge shortcut"?

This will replace your existing 1¼" McAlpine bend on your pan connector to take you to 1½" waste pipe.
https://www.wolseley.co.uk/product/mcalpine-t5m-a-95deg-bend-multifit-x-bsp-nut-15/

View attachment 253451

So is that different to what's already on there?




Thanks for the help

 

[Madrab]

I've got the impression it might be quite a popular "bodge shortcut"?

That's exactly it, it's an easy fudge to use it to empty a basin rather than running a proper waste pipe to the stack. Ideally all waste outlets in a bathroom/kitchen should be run to the soil pipe/stack separately, that minimises the risk of them interacting with each other if one blocks. The turn in a 90deg bend of a pan connector is a great place for restrictions to occur and then cause trouble with the basin.

 

[DIYNotIan]

That explains it then, thank you. I don't think it would be worth the upheaval to do it properly to be honest as it would involve a fair bit of work. It's good to know though. I don't mind getting my hands dirty, delaing with blockages etc. So should it come to it and a problem occur, at least I'll know where to direct my rubber gloves, plungers, and drain rods, etc That being said, we hardly ever (if at all) use that toilet for number 2s so hopefully no problems would occur anyway.

Someone has found this for me:

https://www.wolseley.co.uk/product/mcalpine-t12-bsp-female-x-male-couplng-15-x-1-25/

So my plan now is to stick with 32mm and do the following... From the sink plug hole:


- 1 1/2" - 1 1/4" coupler reducer with flat washer, as per link
- 32mm telescopic P trap
- Connect to existing pipework (which is 32mm) from there, as seen in this photo:




Does that sound like a reasonable plan? Any major problems with having 32mm all the way (not forgetting that the plug hole in the sink has a diameter of 34mm to begin with)?

Thanks for the great help

 

[JimCrow]

Be aware that those pan connectors aren't really supposed to be for plumbing in basins, of course some 'plumbers' use it for that.. That's really to allow a vent to be fitted if there's an overly long soil pipe run etc.

Was that comment for me Madrab?.

 

[Madrab]

Was that comment for me Madrab?.

For the OP

Any major problems with having 32mm all the way

Nope ... that being said, 40mm would always drain quicker. You may also want to consider an anti vac trap.

 

[DIYNotIan]

For the benefit of anyone coming across this in the future who finds themselves in a similar situation, my plan (as outlined a couple of posts back) worked a treat, and I'm set up and all works perfectly.

Thanks one and all for the great help.