Basin waste

[John]

Is it possible to seal a basin waste without using LSX? I prefer not to use goos and gunges - but I guess the thread needs to be sealed.

[Tim Watts]

I'd use LS-X (and did) on the washers-basin interface top and bottom - it's not really a gunge and if you wipe the excess away whilst wet with meths you won't really notice.

Re: the thread:

If the drain does not have an integral overflow, it *should* be sufficient to get a good seal between the drain top (where the plug goes in) and the basin surface.

if you have an integral overflow, then you will need to seal the threads as water can be present on both the inside and outside of the drain insert.

Another option is a good dollop of heavy silicone plumber's grease on the threads and wipe the excess off.

[Tabby]

The thread doesnt need sealing, what needs a seal is between the waste assembly and teh bottom outlet of the basin. Any gloop will do it, eg silicone or plumber's mait.

You can try it without gloop, but after one bucketful you'll do it properly. If youre a gloopophobe you might get it to work with just a rubber ring, but I doubt it.

NT

[chris French]

Yup, that's all I did on my last bathroom install. Silcone twixt the waste and basin, wiped off after fitted (possibly on the underside of the basin as well, can't remember). Quick, easy and not messy.

[John]

Thanks - I realise now that the water is leaking down the thread and the rubber ring cannot be expected to seal the thread - only the face. LS-X will be applied.

[F Murtz]

In the good old days plain ordinary window putty was used between the bowl and the fitting on the upper side,rubber washer on the bottom which lasted years.Threads should not have anything on them, the p trap usually has rubber seals that seals the thread.

[chris French]

In message , John writes

There shouldn't be any need to seal the thread as such, sealinh sould be between the waste and the basin.

[Tim Watts]

It does if the basin has an integral overflow - the drain insert has a hole in the side which means that water will be present on both sides of the metalwork.

Thus it is no longer sufficient to seal the top only - you need to seal the bottom and that includes the threads as the rubber washer won't do that reliably.

[The Natural Philosopher]

Not, as others have pointed out, with an overflow system in place.

Those actually have a chamber below the basin and typically holes in the side of the waste pipe.

So the joint that counts is the one between the waste pipe and the lower side of the basin,

The rubber ring and lots of PTFE tape is a way to go, but its easier to simply pop the waste in, gunge silicone round the hole, apply washer and tighten up. wipe excess off, wait 24 hours, and tighten up a bit more.

[The Natural Philosopher]

And sealing the top is only an issue to keep the basin fill of water with the plug in, forever. Which is not a huge practical problem.

[John]

I have applied LS-X to the thread where it will also be covered by the rubber washer. Hopefully I didn't get any lower down where the nut will fit.

[The Medway Handyman]

Was the basin waste delivered by flying pig? :-)

LS-X applied top & bottom. Unless the instructions say 'sealant is not required', in which case LS-X applied top & bottom

:-)

[andrew]

work. The rubber cone shaped washer squashes into the threads and seals.

A

[The Medway Handyman]

> These work. The rubber cone shaped washer squashes into the threads > and seals.

They look useful - thanks for that.