What is the issue? Your attic should be properly insulated so there should be no issue in the winter I had pex all through my house in Galgary often minus 30 celsius no problem . An attic needs good insualtion no matter where you live since it also is needed for summer heat.

I have Pex and live outside of Houston. No issues with me or neighbors. I’ve noticed in my area that many of the homes that have suffered catastrophic leaks are over 30 years old. I’m not saying there’s not people with Pex who have issues (I’m sure there’s some), but the big problems I’m seeing near me are all with “older” homes.

"What is the issue?" so you don't see any issue lessons learned w/ pex in attic w/ 72+ hours of no power, heat or flowing or dripping water w/ continuous hard freeze temps as low single digits?

Hmmm so let me get this straight - "properly insulated" and it's all good.

I literally had 0 issue with Pex piping with the scenario you are mentioning.

Yeah I was thinking with water lines in attic and an extended multi-day period of single-digit temps with zero power and zero heat that could eventually lead to some water breaks in the ceiling and all the damage that entails. Bursts can occcur anywhere under these conditions - just thinking about the level of damage incurred based on location/routing...