You see the first guy to reply sprinter???
He bought thermopex, it split and failed and became water logged.
He's now wishing he'd went with something else and you see what he's going with, and how he's doing it is top notch! Probably the best way of doing it
You often claim these standards and tests but a lot of that stuff is purely nothing more than a company paying for a certification and nothing more.
The heat loss on z supply 5 wrap is .48 per 100ft at 5 GPM
If you think creating a barrier between soaked wet soil or frozen soil in the form of an air space isn't a good idea, then I simply ask you do some research outside that of marketing labels or paid for certifications
Oh boy I'd love to see some split thermopex, can't imagine what the bedding looked like if the thermopex casing failed. And no way the pex split. A highly qualified installer can make anything fail.
If you think even for a second that multimillion dollar companies throw out bogus ASTM and test data specs for sales, someone has pulled the wool on you. Unless Z supply has changed something on their test data it claims a half a degree loss with a 65kbtu load thru 1" pex. Also their testing data is no where to be found or accredited , just a few details in quotes. They also don't mention whether the test data is with PAP or the cheap pex witha .875" ID . BIG difference in flow velocity. No where do they state a specific pipe, GPM flow and temp loss in the same sentence. Let alone any test conditions.
I'll put up any of the brands I mentioned in a side by side test. I think more research also needs to be done on where and how a reflective radiant barrier will actually work. If there was even a small benefit of using it underground why aren't the big manufacturers using it? We all KNOW what standing or sitting on a single 1" layer of foam board feels like on the ice, or on my toilet seat in the outhouse in Alaska. Last I checked anything foil isn't being used, and I wonder what happens when that pipe makes a bend and the pex presses the foil against the side of the drain tile. I wonder if it makes a hotspot?
I'm not trying to say Zpipe is junk, just that it's not some miracle pipe that works as good or better than the good pipe. We are all trying to make our customers systems as efficient as possible, so why take the risk, cuz it's not a cheap one if something does go wrong. And who gets left hanging.