In housing construction, is it a universal consensus that PEX is superior to copper piping in nearly all applications?
Recently, I've been talking to HVAC contractors in connection with transitioning my home heating system from fuel oil to the cleaner, greener propane. Contractors seem to fall on both sides of the fence: 1) Those that say that the lines connecting the propane boiler to the heating manifold need to be copper, rather than PEX
. Because the water in these lines is a higher temperature than that running, say, through radiant heat coils, it will cause the PEX to expand, creating shifting, noise, and strain on the brass joints and equipment at either end. 2) The pro-PEX crowd. To them, PEX (if it's the higher-quality variety lined with materials other than aluminum), can be used for nearly all household applications, no matter what the temperature of water running through it. Expansion is less than copper, and durability is far
better than copper, despite the fact that copper joints are soldered. Copper acquires a build-up of minerals on the interior walls in hard-water locations--a problem that PEX is largely free of. PEX has nearly supplanted copper in all residential and commercial applications . . . So run the arguments of the pro-PEX camp.
Which of these opinions is more universal in residential construction? Is there any truth to the notion that PEX is a bad idea in lines to the manifold due to strain and expansion? Also, is there a possibility that the pro-copper contractors may be pushing copper for financial reasons, i.e. because it is more expensive and requires more time to install and therefore adds to their bottom line?