Pipe Size

[Fenning]

Hey guys, just a quick question.
We are in the middle of a self build project at the moment and getting ready for first fix plumbing. I intend to use a qualified plumber but would like a little background knowledge to prevent him filling me with BS.
My question is what size of pipe would we reasonably expect for a supply for domestic hot and cold.
The system will utilise an indirect unvented pressurised system and on the first floor will supply three ensuites and a main bathroom.
Will we require a 28mm flow or will a 22mm supply be enough.
I would suggest that in the mornings it will be entirely possible that three showers will be running simultaneously.
Thanks for any help.

 

[numpty1]

i would suggest a 32mm supply to the property,28mm from the stopcock to the uv cly combined prv/strainer and balanced 28mm to the points of use
main bath 28mm
en suite 1 28mm
en suite 2 22mm
ensuite 3 22/15mm depending on layout/lenght
if its a large house a looped hot water circuit with bronze pump and thermostat/timer should be fitted to prevent wastage.

 

[Fenning]

Thanks numpty1,
However please forgive my ignorance.
Do you mean a sperate 28mm supply to each of the bathrooms, or will one 28mm supply meandering through the house with t's to each bathroom suffice.
Also, when he gets to each of the showers wash hand basins etc. is it acceptable to then reduce to a 12mm feed.
The plumber did suggest a looped return from the furthest point from the tank with a pump and timer, so that in itself gives me confidence in his ability / knowledge.
Again I am coming from a position of relative ignorance and do not want led up the garden path.
Thanks again

 

[numpty1]

depends on layout of house plus what he has priced for.
personally i prefer to fit individual supplies to each bathroom/ensuite makes it easier in the future to maintain,if you want the best flow/performance from your appliances reduce the pipework at the appliance and definately not 12mm, 15mm min.

 

[Fenning]

Fantastic, thank you very much.
I am turning into a DIYnot addict, it never ceases to amaze me that people will take time and respond to my ammateurish questions.
Thanks