Noticed the attached today. I'm guessing pipe leaks from the shower that's located behind the wall/skirting. Builder has said we aren't covered as new build over 2 years old. 😬
Yeah, well, they would say that wouldn't they? Hidden pipework that starts leaking is a liability nightmare for builders because it's difficult to dispute claims that the workmanship and/or materials were faulty at the time they were installed and such claims can be made six years (or more in some circumstances) after the work was done. Easiest way for dodgy outfits to avoid liability is to persuade the customer that it's pointless to investigate what their rights really are.
Anyway get your plumbing from a plumber and your legal advice from Trading Standards, your house insurer (if you have legal cover), solicitor, Citizens Advice, etc.
If you use Citizens Advice, remember that they are a charity so, if you can afford it, please make a donation so they can help the next person as well as you.