How long after completing a job should a builder

[JumpRope]

be responsible for things going wrong? We had 2 new bathrooms and some alterations done last year - they finished in about July.

I've noticed a leak coming through downstairs, and had a plumber friend take a look. He said the basin cold tap was plumbed in with the old fitting, and that's why its leaking. Its a pita to fix due to the nature of the pedestal/basin arrangement, otherwise my friend would just do it quickly. But it is the builders fault.

AIBU to call and get him back to put it right after 6 month plus? It clearly an old fitting that's causing the problem, as the other bathroom has shiny new fittings that look completely different.

Yanbu, was a slow leak? As it could have been leaking the whole time and just starting to show now.

Whether he will come back for few is another matter

YANBU

But it may take a lot of effort. A lot....
Bin there done it, including a complete rehaul of the heating system at a cost of £5k because the builder was a useless twat was a complete fuckwit and did a runner did a runner.

Oh no, ARWAV. This builder definitely not a fuckwit, but I was quite a nightmare client I think as I changed my mind a few times, and I think he was glad to be gone. I'm embarrassed to call him back.

My DH is a builder and he would rather know if a problem had developed that might be his fault so he could correct it. He would prefer to maintain a good reputation as most of his work comes from recommendations. Get in touch and give him a chance.

If it is clearly a result of their workmanship (we all make mistakes), they value their reputation and want repeat business and recommendations then they'll come back, albeit rather grudgingly after such a long time. I have a different trade but it's what I'd do. If I thought it wasn't likely a result of my workmanship but difficult to prove/explain to the client I'd still put it right if it only required my time plus a few odds and sods out of the van I'd expect a shed load of the 'post' biscuits for my trouble though If I felt it was clearly not down to me I'd offer a pretty cheap rate to put it right because I'm a mug to maintain my rep and keep them happy.
All depends on how much they depend on their reputation!!

Haha posh not post! Damn autocorrect! I've eaten many a in my time, yet to come across a post biscuit I get a feeling I'd break my teeth!

If they won't come back to have a look or deal with it then consider contacting any trade body \ group they publicise they are a member of.
unfortunately we had to do this when our builder ignored our calls and issues. The tradesbody suspended him until he addressed the fault, which strangely happened very quickly. Ridiculous that it had to come to that but there you go