Basin waste, help please

[NickB_99]

Hi,

In the middle of swapping a small cloakroom basin for a larger basin on a vanity unit.
Struggling with the waste and looking for some advice! It's prob a very basic question, but got to start learning somewhere!

The vanity unit has a piece of the frame in the way where the existing waste comes through, and doesn't look wide enough to cut through, so I've drilled a new hole to drop the waste a bit to fit underneath.

Untitled

• NickB_99
• 31 Jan 2015
• 1

The existing bottle trap is a macalpine one, (I think) an anti syphon bottle trap, but the grey waste pipe seems to be not a standard 32mm - seems to be 34.5mm (outer dia measured with calipers). Are there older sizes or is this expected?

Untitled

• NickB_99
• 31 Jan 2015
• 1

I'm also not sure that the connection of it to the new push button waste in the sink fits correctly. The metal threaded part of the push button waste seems slightly oversized in diameter.

If the pipe is coming through lower, then I'm not sure of the best solution.
Doesn't seem enough room to use the same design of bottle trap, as not enough room to route the waste with a step down to the new hole in the wall.
There seem to be bottle traps that are extendible eg.
http://www.screwfix.com/p/mcalpine-adjustable-inlet-bottle-trap-32mm-white/36251
Wondering if one of these may be easier?

The new basin is further from the wall than the old, so think I will also need some more pipe - but as I'm not sure what size it is, not sure what to buy!

 

[Newboy]

The waste pipe is push-fit rather than solvent weld - slightly bigger OD.

Variable length traps may help - depends on how much lower you need to go. Alternately you may need to modify the waste to allow you to get to the existing waste connection


Not sure what you mean about the waste connection/push button waste

 

[longdogs]

You could try swapping the existing push-fit elbow for a compression elbow which should solve the size difference. Yes, the adjustable trap should do the trick. Connection of the trap to the waste should be standard.

 

[NickB_99]

The waste pipe is push-fit rather than solvent weld - slightly bigger OD.

Variable length traps may help - depends on how much lower you need to go.
Not sure what you mean about the waste connection/push button waste

Only need to drop about 5cm. Will look at the variable length traps. I can take the fitting into my local Screwfix, pretty good at letting me check stuff before buying.

Sorry I wasn't clear, the plug hole in the sink is new and is one you push down to seal and push again to release. It has a metal thread that protrudes out the bottom of the basin and when I tried connecting to existing trap, if seemed that the metal threaded part was larger in dia by 1mm at least.
I think will try a new adjustable trap. Can take in the plug waste to Screwfix and check.
My dad has some spare lengths of basin waste pipe, so saves buying 3m.

Thanks for the help.

 

[Hugh Jaleak]

I'd avoid the cheap Screwfix traps, they can have a tendancy to leak. Go for the McAlpine version, slightly more expensive but better quality.

 

[Madrab]

I'd avoid the cheap Screwfix traps, they can have a tendancy to leak. Go for the McAlpine version, slightly more expensive but better quality.

+1

Yup, for sure, McAlpine all day long IMO

 

[NickB_99]

Thanks Hugh J and madrab, will do.

Funnily enough, when I got the toilet waste pipe connector
last week, it was a sf own brand. As I was heading back to the car,
a plumber stopped in his van and said the same and recommended I change
it for the macalpine - which I did.