BATH DRAINAGE All aspects of plumbing questions and answers, help, tips and information

[martinhines]

I am fitting a new bath the opposite way round from original the pipework to the outside stack is also the original. How difficult will it be for me to drain the bath into this pipework.Can i just run a waste pipe from the waste to the outside wall under the bath, and if so what kind of declination will I need or could I go around the wall under the bath with the necessary declination. I would appreciate any advice on how to acheive this.

regards

martin

[htg engineer]

Minimum fall for a bath/sink waste is 18mm per metre, the max being 90mm per metre.

'How difficult will it be for me to drain the bath into this pipework'
Yes it is possible, but It depends whether it is cast iron or plastic as to how difficult it will be.


Hope this helps
htg

[martinhines]

Hi

Thanks for the reply the bath is steel. Which part of the P TRAP do i take the measure from to the original pipe entering the stack to enable me to calculate the number of mm . I am hoping I could just run the pipe directly along the bottom of the bath. On a second subject I have removed all the tiles this has left a great deal of adhesive on the walls which is verydifficult to remove, can this when made flat be used as a base for the new tiles once any loose material has been removed, or would I be best having the walls replastered. I would appreciate any advice.

best regards

martin

[htg engineer]

'How difficult will it be for me to drain the bath into this pipework'

Cast iron or plastic - i was referring to the stack ??? as you say this is where you wanted the waste to discharge.

I have just done my bathroom a few months back. I removed as much tile adhesive as possible (took a while), installed the bath then I had the room re-plastered this provides a flat surface for re-tiling.

Also plastering after the bath installation, the bath was sunk into the wall - even if only a few mm then with the adhesive and tiles on top of that there should be no leaks when using the shower.

As for the measurment - it's up to you, measure to the bottom of trap, pipe and outlet - or top or middle - if measured to the middle, as long as you measure to the middle of the trap, pipe and boss/soil connection it'll be correct

Also - if tiling, you don't need a bath seal - alot of people use bath seals when the tiles and adhesive are capable of making the seal. Bath seals are always the first thing to discolour and make the bathroom look untidy.

htg

[martinhines]

The stack is plastic Ive measured the declination and should be fine thanks. And for the plastering tip. Just to bug you once more I am planning on taking back all the pipe work back to where it enters the bathroom. I am using push fit copper fittings from B&Q the pipes brining in the water have been painted several times and are disgusting. What process do I need to ensure they dont leak, for example cleaning off the paint on the pipes.

regards

martin

[chris_on_tour2002]

yes, clean the paint off the pipes - i use a combo of heat gun, scraper, sandpaper, wire wool, or whatever means necessary. it can be a pig of a job cleaning up painted pipes but you must remove it all to ensure a tight joint.

also i'd avoid push fit if the pipework is not going to be visible or accessible. use compression or better still solder.

[martinhines]

I share my mains water supply with the flat upstairs and want to take my time putting in the new pipe work. I need to install a stop cock where my water seperates. How can i do this the 22mm pipe supplying the mains is close to the wall so I cannot use a copper pipe cutter. Are there any short cuts on the market which would allow me to turn my water off and not theirs.

regards

martin

[htg engineer]

You would normally have your own stop tap, very unusual if you haven't.

You could attempt freezing, but would have to be away from the branch for it not to affect there water, also if they use the water while you're freezing it it may not work, as the water needs to be static.

I wouldn't worry too much, to fit a stop tap will only take minutes - can't see anyone objecting to that.

22mm pipe slice (https://tools4trade.com/shop_productdet ... pid=119013) should get in to a pipe close to the wall, if not a hacksaw will do it.

htg