Starting to think about our en-suite now. We currently have a couple of pipes that run under the floor;

 

- Hot and cold to kitchen below (ancient pipes, at least 30 years old, I believe they're 15mm copper, or equivalent). Water in the kitchen sink takes an age to run hot/cold, so something not quite right here. Run is approx. 18m. I believe these pipes also service the existing en-suite basin/toilet/bath.

- Hot and cold to existing shower (22mm HEP fitted, last year, direct to the Trevi mixer). These two certainly don't do anything but service the shower. 

 

Selfishly, my priority is the shower, I want that to take priority if anything else is calling for water upstream. So with that in mind, I think a single 15mm tee from our existing 22mm to service "everything else" would be my best bet;

 

 

But, based on advice I had when doing our Utility room, I think having all outlet's teeing into the 22mm would be the "proper" way to do things;

 

 

 

The kitchen will have sink, dishwasher and cold outlet for the fridge. Utility room and downstairs W/C has been tee'd off already downstream on the existing 22mm HEP. 

 

Thoughts, opinions? Alternatives?

Still leaning towards option 1 unless anyone can persuade me otherwise (and I'm easily swayed....)

I'm no plumber and don't have any kind of practical experience to fall back on, but would option 1 have problems with flow if outlets are used concurrently?  Thinking about the plumbing in my olde bungalow it's more along the lines of diagram 2, 22mm main with 15mm branches.

3 minutes ago, crispy_wafer said:

I'm no plumber and don't have any kind of practical experience to fall back on, but would option 1 have problems with flow if outlets are used concurrently?  Thinking about the plumbing in my olde bungalow it's more along the lines of diagram 2, 22mm main with 15mm branches.

 

Yeah, I almost want that so I can have a decent shower above all else I do agree that option 2 would be "preferred"

Wouldn't bother with the 10mm feeds to the toilets as it's an extra set of fittings (15-10mm reducers x2 for each, inserts, pipe etc.) Only other input would be to run 22mm pipes to the bath.