Before we could start laying hardcore in the extension’s floor area, we needed to move the main water supply pipe from the back of the house.
The existing stopcock and pipes were buried in concrete beneath the bathroom floor at the rear of the house, so we needed to find another point where the supply could connect to the plumbing. We found a cold-water pipe running down the kitchen wall below the boiler that looked like a possible connection, at least temporarily.
Using a core drill, we drilled through the kitchen floor and down through the cavity wall, emerging at the side of the house about 50cm below ground level. We then cut the lead supply pipe and connected it to MDPE water pipe, which we fed through the opening into the kitchen inside ducting. Finally, we fitted a new stopcock.
There were a few leaks at the new joints to begin with, but we managed to sort them out and finish as night fell.
I was still nervous about the connection. I spent much of the evening staring at the new stopcock, waiting for the whole thing to come apart, and got up roughly every half hour during the night to check it.
So far, though, it has stayed leak-free.