PEX QUESTION

[Robert Olin]

If I use a manifold system, can I eliminate individual shut off valves, like under the sink or at the toilet? Is the code man ok with that?

What if I use the manifold for an area like one bathroom?

Let say I have a typical bathroom on one manifold. If the pex is 1/2" I assume that is adequate for the toilet and sink, but I'm wondering if a tub or shower should have their own dedicated hot and cold back to the manifold?

Thanks, Bob

[DD_BobK]

I would suggest you search this ng for threads on PEX. Many of your questions have been answered.

I've done a couple pex whole house re-pipes. I even thought about eliminating "local shutoffs" (aka angle stops). I decided to use angle stops with a manifold system and I'm very glad I did, the convenience is worth it.

Depending on the house layout, a single manifold could serve for the whole house.

Even with local manifolds, I would recommend shutoffs.

BTW if oyu choose to use manifolds, they get used in paired sets; hot & cold. So a house needs a hot manifold & a cold manifold. Same with local manifolds

1/2" PEX is fine for a tub or shower, even if the runs are ~30 to 40 ft.

visit

take a look at the plumbing manuals, good stuff

cheers Bob

[jamesgangnc]

I'd put the cutoff on no matter what.

[Oren]

Yes and Yes (if local codes allow PEX).

My house is a PEX manifold system. All lines are a home run from the manifold - 11 cold and 9 nine hot supply lines. I have no stop valves at any water feature. I can turn them off at the manifold (central location in the laundry room) or turn the house off in the garage and at the street meter. House is built early 1997, single story.

Each supply line hot/cold is a home run from the manifold. Think octopus tentacles :)

[Oren]

I haven't seen "paired sets". My manifold is a single unit. Hot on the left and cold on the right. I guess if is molded fiberglass.

I've seen some really nice manifolds made of copper with brass ball valves (good plumber) at the manifold. They were cobbled together on site for near 5K s.f. homes.

[DD_BobK]

What I meant by "paired sets", I meant two separate copper manifolds. One for hot, one for cold.

I totally forgot about the plastic "combo" manifolds.

I know the copper manifolds with the built in ball valves are a lot more expensive (about $150 more for two copper manifolds vs the manibloc) but the copper manifolds are much better material. I recommend using the copper ones.

cheers Bob