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roundkat
Feb 17, 2009, 03:27 PM
I have been reading the "RePiping with Pex" thread and have some questions..
I found the link to the PEX pdf but will read tonight..

We have an old house that has under the floor coper, the house has developed to leaks in less than
A year.
The plumber suggested replacing all the water lines with PEX and abandoning the
Under Slab

My Brother in Law are doing the Tear out..

- Location Oklahoma City (about 1700 sq ft)
- We are not doing a "Home Run" or "Manifold due to space requirements
- 2 Full Baths
- Kitchen w /Dishwasher
- 2 outdoor Faucets
- 1 Refrigerator supply
- Attic has about 30" of blown insulation.
- Incoming Supply is a in Bathroom under vanity. (think it is 7/8"
- Hot Water Tank is in Garage - about 30' away

My questions
What size of PEX should I use

We are looking at using 1/2' everywhere
Except using 3/4 from Supply to Hot Water Tank
Will this work

I can provide ASCII art if needed.

Much thanks

Rk...

Milo Dolezal
Feb 17, 2009, 08:40 PM
I would run it as follows:

Cold water: 1" main run, distribute to each plumbing fixture with 1/2" branches. But Water heater 3/4" supply. Shower 3/4" optional. Hose valves 3/4". Washer 3/4". You can go to smaller diameters in main run as you pass w/h , w/m , and 1st bath.

Hot water: Start with 3/4" and tee off to each fixture with 1/2". Once you pass washer and 1st bath, you can reduce to 1/2". Insulate hot water runs.

roundkat
Feb 18, 2009, 04:58 PM
As we got into it we found that we could abandon the 3/4" under the slab
and reuse the copper "branch" which is 1/2" copper.
We only have to run 5 PEX lines of any distance.

Much Thanks,
Rk