Hi all. Currently working on a new second floor bathroom as part of an addition to my home. I plan to use pex for this but it will be my first time with the material. Presently, the plan is as follows:

1) Transition from existing 1/2" copper pipes in basement ceiling below new bathroom.
2) Run a single hot and single cold pex line from the copper pipes up a first floor wall to the second floor bathroom wall.
3) Connect these pex lines to a mannifold. Branch off from mannifold to shower, double vanity, and toilet.

Pex lines will be 1/2". Mannifold will be accessible through room adjacent to bathroom (removable panel in back of a closet). From Home Depot:

1/2" Zurn pex tubing - http://www.homedepot.com/h_d1/N-5yc1v/R-100549747/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

Sioux Chief fittings - http://www.homedepot.com/h_d1/N-5yc1v/R-202313186/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

Plan to more or less follow this guide - http://www.siouxchief.com/Resource_/ProductMedia/115/PEX%20Installation%20Guide%205-05.pdf

Any input is appreciated, I want to make sure to get some advice from people who have done this before. Are the products listed okay? 1/2" all right? Thanks!

Everything seems fine except for you should run 3/4 lines to your manifold and use a 3/4 manifold with 1/2 takes offs, then run 1/2 to each hot and cold on each fixture.

Thanks - that's one of the things I wasn't sure about, I'll make sure to do as you suggest. I take it it's okay to use 3/4 pex off a 1/2 copper?

Hi Lee...

MGD77 is "spot on".. use the 3/4" PEX and yeah, purchase 1/2" copper x 3/4" pex adapters to make the transition to PEX. Here, the inside diameter of the 3/4" pex FITTING is actually pretty close to 1/2" which is why it would have been a bad idea to run only 1/2" PEX up to the bathroom as the inside diameter of these fittings is closer to 3/8"... ;)

Be sure to PRESOLDER copper fittings BEFORE using the PEX pipe/crimprings, etc, OK?

Mark

Hi Mark - told you I'd be back! (you just helped me recently with some drain design - thanks, so far so good with that part of it)

Could you explain what you mean by 'PRESOLDER copper fittings BEFORE using the PEX/pipe/crimpings, etc.' suggestion? Are you referring to a special type of fitting that is pre-soldered, or to something I would do to the fitting before installing it?

Hi Lee

Mark is probably out making his fortune, with the cold weather he is very busy.

No, he means do your soldering first and let fitting cool before attaching the PEX. Heat will damage PEX.

Got it - thanks!