Madrab, I appreciate the reply.
Current install is a mixture of Polypipe and Floplast, but they both seems as bad as each other.
I’d guess the oldest pipework is 5 years and it’s looking seriously ropey - if I brushed against it I’m sure it would break which is why I want to replace the lot…...
I’d like to replace all of my external 40 mm waste pipes; kitchen drain, washing machine, bathroom sink & bath/shower, with something that is going to last.
The solvent weld stuff that is readily available from the sheds seems to last a couple of years before breaking down and becoming brittle...