Shared water mains

[nopunintended11]

I share my water with several neighbours with the mains stop cock on the pavement outside our victorian semi-detached properties. We also have our own internal stop cocks.

I am looking to do some extension work. Will this pose a problem or can I just stop the water from internally or will the water company need to install new pipes and how costly will this be?

[Fourbyfour]

You need to contact your water company to ask. Most have a Developers department you need to ring for advice on extensions etc.