I heard/read some time ago, that it's not a good idea to have copper pipes resting on other copper pipes where they cross. (IIRC something about friction???) I discovered this occurring, and was able to get a piece of foam pipe insulation in between the pipes. Last summer, I had a bathroom reno done. This morning I saw that a copper supply pipe (old) was resting on both a hot and cold Pex supply pipe where they crossed (the Pex was secured to the bottom of the ceiling joists, the copper run between the joists.) Questions: Was I right or wrong about the copper on copper not being a good idea? Should I try to insert something between the new pex and the old copper? Any suggestions as to what? As always, thanks in advance.

Hi, I'm going to attempt cut this pipe before it enters the ground, rerun the pipeline to the right (as indicated by my finger pointing) along the exterior of the house, and finish the line with a hose bib/spigot. (I've checked that the pipe is indeed water [u]and not gas[/u]) I also understand that in order to run copper piping, a dielectric union will be needed. My questions: 1. Where's the most sensible place to cut the galvanized metal - [i]with minimal dealings with the other joints[/i] - to connect to copper pipe? I guess I'm asking where I should put the union without having to do too much alteration to the existing pipe coming from the house? * See below, second image - should I run something as shown in orange, brown....or something else? 2. What size pipe is the pipe am I dealing with. I've measured the outside of the pipe and want to run 3/4" copper pipe. Thanks in advance for the advice and assistance. Should I run the copper as shown in the brown route, orange route, or some other route?