External waste pipe elbows disintergrating.

[Simon T]

I've just had to replace all the external 45% elbows on the sink and bath wastes to my house, where they connected to the main waste downpipe.

All of which had virtually disintegrated and some of them had been leaking badly for some time. Just looking at the back of the neighbours house, the elbows on his external waste pipes look in a similarly bad state

These houses are only about 12 years old or so, is it normal for plastic waste fittings to perish so badly in this time?

[Brian Gaff]

Yes.

Probably fitted a load of crap ones. Brian

[Onetap]

uPVC (I think it is) and some other plastics degrade in ultra-violet light. It has to be painted or covered if installed outside. Check the manufacturers instructions.

[Dave Liquorice]

uPVC should be stable its ABS and the like that are not and should be painted/covered when exposed to daylight.

[Phil L]

Pretty much, yes. Those on the North side of a dwelling never rot, because it's the sun that causes it, so paint your new ones

[Roger Mills]

Sounds like they've used some which are affected by UV, and only intended for internal use.

[Simon T]

Any particular paint?

[Phil L]

Not really, just a standard undercoat and gloss for exterior use is fine

[Andrew Gabriel]

If you can still find it, high volatiles oil based gloss, top coat only. It will solvent-weld to the uPVC and ABS, and won't ever peel off.

[Onetap]

Looked it up, it's polypropylene that disintegrates, uPVC CAN (it says) be formulated to resist UV.

If the elbows are that bad, they need replacing rather than painting.