Hi. I'm refurbishing an Edwardian terrace and need a little advice from you lovely people on my plumbing scenario please. I have found some info by searching but not a definitive answer.
I have a kitchen (with combi boiler) and two bathrooms to plumb CW supplies from scratch. The bathrooms occupy the same footprint on the first floor as the kitchen below.
My plan is to split the rising main below the stairs into two 22mm supply pipes - one for bathrooms, one for kitchen.
DOWNSTAIRS - take 22mm direct to boiler (6m run), teeing 15mm off just before boiler to supply sink, washing machine and dishwasher. These would be throttled back in an attempt to keep the boiler best supplied.
UPSTAIRS - take 22mm up and through bathroom area, teeing off in 15mm along the way for all supply reqs.
1st tee will supply small bathroom - basin, toilet and electric shower (toilet and basin throttled back). Theory here is in small bathroom you wouldn't be using the shower AND toilet AND basin at the same time.
2nd tee will supply bar mixer shower in large bathroom.
3rd tee will supply basin and toilet in large bathroom.
Final tee/end will supply bath in large bathroom.
The rising main under the stairs is lead - approx 22mm external diameter. This goes to 15mm copper before and after stop cock. A plumber did a pressure test last year straight off this 15mm copper and he said it was "very good". Can't give you litres/min but could give you that on Monday if I test myself. I have no plans to replace the lead supply pipe. I'm not moving into the property and I have a huge list of stuff to do without adding more to it if possible!
My two big questions are:
1) Given that the inner bore of that lead supply pipe is probably no bigger than the 15mm copper it's attached to, is it pointless using 22mm anywhere? Can I just use 15mm throughout?
2) Does my plumbing plan above sound ok, given my theory on prioritising the supplies so they don't starve each other?
Many thanks in advance!
Cheers, Lubemonkey
I have a kitchen (with combi boiler) and two bathrooms to plumb CW supplies from scratch. The bathrooms occupy the same footprint on the first floor as the kitchen below.
My plan is to split the rising main below the stairs into two 22mm supply pipes - one for bathrooms, one for kitchen.
DOWNSTAIRS - take 22mm direct to boiler (6m run), teeing 15mm off just before boiler to supply sink, washing machine and dishwasher. These would be throttled back in an attempt to keep the boiler best supplied.
UPSTAIRS - take 22mm up and through bathroom area, teeing off in 15mm along the way for all supply reqs.
1st tee will supply small bathroom - basin, toilet and electric shower (toilet and basin throttled back). Theory here is in small bathroom you wouldn't be using the shower AND toilet AND basin at the same time.
2nd tee will supply bar mixer shower in large bathroom.
3rd tee will supply basin and toilet in large bathroom.
Final tee/end will supply bath in large bathroom.
The rising main under the stairs is lead - approx 22mm external diameter. This goes to 15mm copper before and after stop cock. A plumber did a pressure test last year straight off this 15mm copper and he said it was "very good". Can't give you litres/min but could give you that on Monday if I test myself. I have no plans to replace the lead supply pipe. I'm not moving into the property and I have a huge list of stuff to do without adding more to it if possible!
My two big questions are:
1) Given that the inner bore of that lead supply pipe is probably no bigger than the 15mm copper it's attached to, is it pointless using 22mm anywhere? Can I just use 15mm throughout?
2) Does my plumbing plan above sound ok, given my theory on prioritising the supplies so they don't starve each other?
Many thanks in advance!
Cheers, Lubemonkey
