replace sink waste and change from plastic to metal

[happyhero]

Hi can anybody help me? My father wants me to help him replace his plastic waste pipes in the alley way at the side of his house. He has 3 waste pipes coming out the wall from 2 sinks and the bath. One of them is metal painted black, the other two are old white plastic. I don't know how old they are but they have gone a funny colour and are very brittle with the odd hole in them now, so really had it.

I said it would be easy to replace the plastic but he is very insistant that he wants to change them to metal like the other one. I tried to measure the diameter of the old plastic pipes and they appear to be 35mm.

So my questions are:-

Did it used to be 35mm or is it just 32mm badly measured by me?

Can I get metal waste easily ie B&Q and all the joints?

How do you put the metal ones together?

And assuming it is plastic coming through the wall, how do I make a watertight joint from plastic to metal?

Any help appreciated.

 

[Nige F]

The metal ones --copper-- scratch and see you can get 35+42mm copper but it`s £££ and the fittings are soldered like the small stuff 15mm-----------you can get MacAlpine plastic bodied compression fittings for waste pipe--- fits anything to anything.......may have a website

 

[Expertboy]

I know Wickes have 35mm plastic waste pipes !!