Plumbing 2 baths on second floor to minimize water pressure drops

[Jwray]

My house currently has 1 full bath on the second floor. I am changing that situation to 2 full baths on second floor plus a 1/2 bath on first floor. In the process I am redoing all of the supply and drain plumbing (entire house). I'm almost through with the DWV and doing some supply planning.

When I am done I want to have a setup that minimizes pressure drops in the shower (especially) and lavs with toilet flushing, dishwasher and clothes washer running etc.

Here' the final configuration:
Basement - hot water heater, clothes waser, and laundry sink
First floor - 1/2 bath, kitchen sink, dishwasher
Second floor - Guest bath: tub/shower, toilet, vanity
Master bath: shower with 2 heads, toilet, 2 vanities

I should also note that the way the plumbing will route (at least the easiest way - could do other if it will help with pressure) to the second floor baths is:

Guest Bath - lav, then toilet, then tub/shower. I could also easily pickup the master toilet and lavs from this run, but this might be too much for 3/4"?

Master bath - the layout is such that the toilet is first and then the 2 lavs are to one side and the 2 shower heads are to the other side

Should I run a separate 3/4" hot and cold line to second floor for each bath and then go to 1/2" at each fixture?

I'll be happy to supply additional info anyone wants. I appreciate your time and advice.

Thanks,

Joel

 

[Finnegan]

I was faced with a similar dilemma when plumbing my own house. I opted to bring one set of 3/4" lines up to the two second floor bathrooms. I thought it made more sense to minimize the amount of pipe. I wanted to avoid stagnant water in the pipes and the annoying wait for hot or cold water. As you can see I did not opt for a hot water circulation system.

 

[Sponsor]

 

[TheZster]

I imagine your main interior line is 3/4 inch... which is pretty "honkin big" as far as water supply goes - though 1 inch is even better...... If it were me..... I'd run single 3/4 as close to the "end user" and branch off of that with 1/2 to your units...

Then again, depending on where you live....... I'm now in a house with Pex flex tubing.... and love it. Each fixture in the house has a dedicated 1/2 inch line running to a central manifold. No pressure drops..... and quick, quick hot water.... It's "spendy" compared to copper - but installs in no time at all... without leaky solder joints (if you're a "weekend plumber")....

Not a plumber.... so take it with a grain of salt.......