I have an attached exterior laundry room on my back porch housing the water heater, washer and dryer. I replaced some corroded galvanized fittings for the hot and cold water connections on the WH and after that was compete, I noticed some water leakage in the wall on the hot side. This house was built in the late 50s. After tearing out the sheet rock to expose the pipes, I see that I need to re-plumb this whole laundry room's crumbling galvanized pipe with modern plumbing.

I've done plenty of PVC and CPVC plumbing but I have never messed with Pex. This room is poorly insulated and while Austin, TX does not get hard winters we still do get hard freezes on occasion. Does Pex tubing and fittings have better freeze resistance than PVC? All the supply pipe is in the attic, due to the low roof I will need to cut out the ceiling sheet rock to do this. There is existing black iron gas pipe that I will leave alone other than to add some support and strap it down solidly.

I estimate the total run at 40 feet or less  (20' hot, 20' cold) with a 90s down from the attic, Ts out to the WH, 90s over to  the  washer and whatever fittings out to the washer hose barbs.

Would something like this work for crimping Pex for a little project like this or is it cheap trash?
http://www.homedepot.com/p/SharkBite-3-8-in-1-2-in-and-3-4-in-PEX-Copper-Crimp-Tool-with-Integrated-Go-No-Go-Gauge-23383/205435373


Gringop

PEX is more resistant to freezing than PVC pipe. It is the preferred plumbing for new construction.

I prefer PEX, less worries of freezing and busting.

Pex for sure, I worked with it the first time just over a year ago. Super easy, I also got the tool from homedepot also.

I have worked with both and would prefer pex for quick completion (no waiting for the glue) and freeze resistance.  Copper crimp rings and brass fittings.

PEX for sure.

Pex supposedly expands better and therefore is supiorer. It also is super easy to work with, although so is PVC in comparison to copper and other stuff. The downside is that pex and the fittings are so (relatively) new that there isn't much data on long term reliability. There are Copper water lines all over the country that are over 40 years old or more and working fine. Pex has a long way to go to gain this type of reliablility, but looks good so far.

Honestly though, why not insulate while you have wall down if not already done. I will further ensure that your pipes won't freeze, help regulate heat loss in the hot water line and help with cooling/heating costs in the home?

If I didn't install copper, I would use pex.

This.

Pex X 1,000 stuff is easy to cut easy to work with and easy to make clean looking!!!