R. Cott 18

[Tim Lamb]

First fix plumbing...

Pipe sizing. Recent holiday cottage was plumbed in 15mm at mains pressure (I think). Toilet flushing was particularly noisy with the cistern valves slamming open and shut and noticeable flow noise from surface mounted piping. (quite an issue for men of a certain age!)

A pressure regulator may solve most of this but what about bath fill time? Having lived with long runs of 22mm on low head with 2 gallon draw off before the hot arrives, I am trying to minimise run length and pipe size.

Thermal store is roughly in the middle of the house. Advice so far has been to use 22mm for mains intake to distribution point. Will I get away with 15mm for separate kitchen and bathroom feeds.

I don't know our mains pressure but we are at the bottom of the hill so get what there is:-)

[Tim Watts]

I regulate my mains down to 2 bar and 15mm from a central dist point fed by 22mm from the incoming is more than enough for anything. I even have flow reducers (adjustable by switching tiny cartridges) to slow the basin down more to avoid splash back.

[Tim Lamb]

OK Tim. That is reassuring. For historic reasons, I actually have two mains water intake points. One will be used for kitchen drinking water only and the other everything else via the water softener. We never did resolve the mystery of the blackish deposit on the toilet I think is fed from the soft supply. I have since wondered if a slight leak into the toilet bowl could evaporate leaving the deposit which a flush does not have time to dissolve fully.

My longest pipe run will be around 8m but that does not feed a bath.