I’ve been moving more and more to using PEX for my customers and yet I have a question that keeps popping in my mind. Is 1/2″ PEX the same as 1/2″ copper in terms of flow rates, pressure, etc? Same with 3/4″ PEX, is it the same as 3/4″ Copper?
I ask because the fittings for PEX that you crimp to are noticably smaller in diameter. I didn’t meaure it but it almost looks like a 1/2″ PEX fitting has an opening that is like 3/8″ ID which to me is not the same as 1/2″ copper.
A side question to this then is, when planning an installation with PEX, because of the above, do you have to calculate pipe size vs. fixture units differently?
I been in a few houses recently that plumbed with 1/2″ just about everywhere and wondered if it’s still somehow equivalent to copper.