I'm going to fit a new basin, with monobloc tap and lever-operated pop up waste. The Waste that comes with the tap has two thin foam washers with it. Should I use these top and bottom of the waste? Or should I use some Plumbers Mait? And if yes, should I use the Mait top of waste, bottom of waste, or both? Thanks for any advice. I want to get it right, as I've had waste leaks top or bottom before on new basins. Usually when I just used the supplied washers. Would like the advice of the experts.
This is my way of doing it, which I've found successful: 1. Buy a "Basin Mate" to go under the basin. 2. Discard foam washers. 3. "Sausage" of Plumber's Mait around underside of waste fitting flange. 4. Fit waste with smaller cone side of basin mate going into basin waste hole. 5. Do up reasonably tight. 6. Mark where bottom of basin mate comes on threaded shank of waste fitting. 7. Remove waste, and smear a little Plumber's Mait around threads above mark. (To stop splashes from overflow dripping down thread) 8. Reassemble and final tighten. Remove excess Plumber's Mait (use white spirit and sharp knife). 9. Make sure slots in waste are lined up for overflow and remove any trapped Plumber's Mait (otherwise overflow may not work properly). 10. Fit "pop up" mechanism. 11. Fit waste pipework. Make sure pop up mechanism does not interfere with tightening trap to waste. If necessary buy and use 1 or even 2 additional rubber washers in trap flange. 12. Test. Should be leak free. If not identify and correct cause.
Thanks for your comprehensive instructions. Shouldn't leak after that. Can I just confirm that the Basin Mate sits up under the hole in the basin, then the big brass piece with mechanism inside screws up under it? Will the thread on the waste be long enough with the addition of the Basin Mate? Because the big brass fitting with mechanism now sits further away from underside of basin (because Bain Mate in between), will the lift/drop mechanism for plug still work OK?
>>>>>>>>>>>>>andy48. Thanks again. All done. Only thing I did differently is put some a small smear of silicone around the bottom of the Basin Mate where it meets the thread of the waste. Couldn't be bothered to prise the rubber back off the thread to put Plumbers Mait on thread as it was so tight to get on there and force it up into the waste hole. Ooooer, missus!! Managed to break the plastic collar that came with the B M, not sure how. The waste's back nut seems sufficient to hold it all together. No leaks though - that's the important thing.