Main water feed pipe under extension

[plasticpete]

Hi,
Just had a leak detected on my property between kerb stop cock and an ouside tap. About 6 years ago, and before I moved in, the bungalow was extended about 1.5 metres sideways along it's whole length. The water supply now comes from the main stopcock, under the living room floor, under the bathroom where it tees of through another stopcock for the internal supply. It then continues under the bedroom floor and outside to a wall mounted tap (stupid, I know, but the tap doesn't even have a shut-off valve, so it's fed directly from the mains!)
Guess where the leak is ..... yep, under the bedroom floor, just before the pipe goes outside!!
My question is, were there any building regs in force in 2009 (when plans were submitted) which would have required the owners or builders to re-route the supply, or were they OK in building over it?
I'm exploring every possible scenario as my buildings cover only covers accidental damage, but, as I didn't get a buildings reg certificate when I moved in, I've got a certificate indemnity policy. Naturally I'm hoping someone else is going to pay to re-route the supply, but I'm not holding my breath!
Sorry to be so long-winded.
thanks in advance.

 

[plasticpete]

Sorry, forgot to say that the floors are solid, of course!

 

[vinn]

What material is the water main? Are you looking for advice on fixing the leak? or where and how to run a new main?
These retrospective hunts for who's responsible for what usually dont have happy endings.

 

[plasticpete]

The main is one of the "polys". Looks to be about 30mm, though I've not had my arm down to measure it! Prefer not to do it myself so I was looking to find out if there were any building regs in force in 2009 (when plans were submitted) which would have required the owners or builders to re-route the supply, or were they OK in building over it?

 

[Tipper]

I think the Water Regulations 1999(?) may be what you're after.
But I also think you'll have a long battle getting any cash out of your indemnity insurance as this usually only covers the necessary legal costs to fight a battle...but with whom?