On Sep 10, 9:36*am, Tim wrote:
* Hello again,
* *I am continuing to gather info for the new house,this time
concerning plumbing. I had been thinking about the Manablock
system,basically a plastic(PVC) manifold known as a "home run" system
in which there are seperate shut off valves for every outlet and, I
assume, fixture. The piping is flexible Pex tubing,which seems like a
good idea,but the Manablock sys. seems to use a whole bunch of
tubing.
* I spoke with a guy from a plumbing supply place today who said that
many plumbers today are using the Wirsbo system which utilizes 3/4"
trunk lines to smaller manifolds that I assume are located close to
the areas they will supply,branching off into 1/2" or 3/8" tubing to
supply the end fixture.
* Does anybody have experience w/ these systems,or can you lead me to
a resource for more info,perhaps a newsgroup such as this(I looked but
didn't find a plumbing newsgroup) * *Thanks again for the info.

Tim

Tim-

I'm an mechanical engineer & avid DIY'r (personally restored a couple
older homes)

The "best" PEX layout / installation depends on:
the design of the house (ex. ranch vs 2 story; "small" 1 or 3 bath
vs 4 or more),
location of the water usage points,
type of construction (slab, raised foundation)
local climate; temperature swings

I've done two home run systems (design & installation)
I've done one "remote" manifold system w/ hot water loop (design only)

those plastic "maniblocs" look enticing price wise (the copper
manifold with shut off are really pricey but I've used them both
times)

I think you'd be very hard pressed to build a copper manifold cheaper
than buying one

From your second paragragh sounds like you're on the right track.

the wirbso site has some design manuals to down load

One bit of advice....when building a home run system, even with remote
manifolds, smaller fixture supply tubes from manifold to fixture will
minimze hot water wait times.

I use 1/2" from manifold to fixtures everywhere, no flow problems &
short wait times

Bite the bullet & go copper manifolds w/ shutoffs...you'll be happier

I recommend the cold expansion with PEX reinforcing rings rather than
the crimp ring systems. I also recommend the brass Pro-Pex fittings.
I got all my stuff online at pexsupply.com (was before locally
available at plumbing supply houses)

you can rent a hand expander or buy one on Ebay & flip it

the design guide that Rico suggests is awesome......a lot of info in
one reference


cheers
Bob