Progress,  page 66
The copper plumbing is now about 95% complete throughout the house.  It will be interesting to
see how many leaks we have when we turn the water on.          (later note: we had four of them)

We ran 1 inch rigid copper from the main water entrance to each of the two water heaters, then
used 3/4 inch rigid copper from there for all the hot and cold lines to the various fixtures.  Each
water heater serves about half the house, and there is a valve on each 1 inch line so that water can
be shut off to only part of the house at a time.

On each line at each faucet is an air piston to absorb impulse shocks ... you can see them in this
picture as the capped vertical lines that are roughly four feet long.  Our well and holding tank are
120 vertical feet up the hill above us so gravity alone gives us about 60 psi to the house, less
whatever friction there may be in the lines.  It's enough to make me concerned about pressure
pulses when someone shuts a faucet off abruptly, hence the air pistons.
Placing the copper lines in the foam walls was easier than I thought it would be.  We used an old
soldering iron with a loop of #14 copper wire to make a simple hot knife and it worked fine.  This
pair of lines is for a corner sink in our son's bathroom.