Do I have a claim-NHBC-advice!

koalakoala

I’ve never had success with NHBC😕

MysteryMe

If it was substandard construction the roof would have leaked before now I'd have thought

stuart45

https://forums.moneysavingexpert.com/discussion/comment/82187994#Comment_82187994

Not necessarily. For example, back in the 70's single lap tiles were only fixed at the perimeter and most lasted for years without any problems. However, a storm could damage them, so fixing requirements are much stricter under BS5534. Some subbies with still just nail every 3rd course if they can get away with it, but technically it doesn't conform to the NHBC standards.

Section62

https://forums.moneysavingexpert.com/discussion/comment/82187994#Comment_82187994

There's something a bit odd because in theory a cracked tile on a modern house shouldn't cause leakage into the loft and rooms below - one purpose of the membrane is to redirect any water which does come through the tiles so it flows down the roof and then over the eaves tray and into the gutter.

In severe weather rain can get through gaps in tiles - they don't need to be cracked for that to happen - but if the membrane was properly laid and remains intact then the rain shouldn't be getting inside the roof space.

stuart45

I'd agree, the membrane must be damaged. Once a roof is felt and battened it's virtually watertight before the tiles go on.