Should I increase extension plumbing to 22mm

[Callummc]

Ive extended my house and need to run the plumbing, I will tee off from the main house which is 15mm, I'm wondering if it's worth increasing it to 22mm with 15mm tee offs to the outlets, or should I just keep it all 15mm, I'm wanting water pressure and volume to be better if multiple outlets are used. I need to run 2 sinks, electric shower a toilet and outside tap..
The extension is a self contained flat thats part of the house.

Thanks, callum

 

[ShaunCorbs]

What’s the incoming water situation like as you will only get out what’s put in

 

[Callummc]

What’s the incoming water situation like as you will only get out what’s put in

The water pressure and volume all round the house seems good and have never had any problems.

 

[ShaunCorbs]

Even running two outlets at the same time ?

 

[Callummc]

Even running two outlets at the same time ?

It does but its not too bad

 

[ShaunCorbs]

It does but its not too bad

Might be worth looking at install an accumulator and running a new 22mm service

 

[Callummc]

Might be worth looking at install an accumulator and running a new 22mm service

Thanks, so would you step up to 22mm to give the extension a 22mm supply via an accumulator and pump, then tee ING off to the outlets in 15mm? What size accumulator would you go for?
Cheers

 

[ShaunCorbs]

Cold water yes hot will be fine on 15mm as you haven’t said the source and you would size the accumulator for both properties