I am going to be running a hot water line up and over from the water
heater to a kitchen sink about 90 feet away. Presently the water goes
through a 3/4 copper pipe buried in the concert slab. I am going to run
a 1/2 inch overhead pipe covered by insulation. I am doing this to get
hot water faster - and not lose a lot of heat to the concrete slab.

I am the guy that was asking how much water is in a 1/2 inch by 100 feet
copper tube.

I went to Lowes and Home Depot and talked to the help there. I have
always used copper in the past sweating my own fittings. Both places
asked me to consider CPVC - it is much cheaper and they said easier to
work with. Is it durable?

They also showed me coils of copper tubing - in K and L category. What
is the difference in K and L copper tubing? It is more expensive than
CPVC - but you would have only one coupling overhead - not like the CPVC.

They also showed me union joints that join CPVC and copper.

I appreciate comments on this job.

Harry