I'm helping a friend who has a 1930s terrace shop, with a 2 bed flat above. He wants to convert the shop downstairs into a 2 bed flat as well. The plumbing in the flat and shop haven't been touched for 50 years.
The water supply comes in under the downstairs shop floor. There is a stop tap 2 feet from frontage inside front door, a lead pipe then runs under the shop floor to the back, which feeds the shop's outside loo, and also goes up to the flat above.
He wants to disconnect the lead pipe at the stop tap, and put a new pipe up through building, into loft then acrooss roof space, then tee 2 pipes off. Each of these 2 pipes will drop down to feed each flat.
My question is can the new pipe from the stop tap, up to where it tees in the loft, be in 15mm, or does it need to be bigger (eg 22mm) as it is supplying 2 flats?
The water supply comes in under the downstairs shop floor. There is a stop tap 2 feet from frontage inside front door, a lead pipe then runs under the shop floor to the back, which feeds the shop's outside loo, and also goes up to the flat above.
He wants to disconnect the lead pipe at the stop tap, and put a new pipe up through building, into loft then acrooss roof space, then tee 2 pipes off. Each of these 2 pipes will drop down to feed each flat.
My question is can the new pipe from the stop tap, up to where it tees in the loft, be in 15mm, or does it need to be bigger (eg 22mm) as it is supplying 2 flats?
