Hi buffalobill. Thanks for the suggestions. I am thinking of calling
a plumber, if only for advice. The interior plumbing is mostly
repiped. I will be terminating in a remaining galvanized section, soon
to be replaced.
You are correct, the original installation used 1/2" running to the two
bathrooms, and there was some advice to go with 1/2" . I installed one
section of 1/2" to the washer with many elbows, and the flow rate was
awesome. Also, both bathrooms had sufficient flow with the original
1/2". Code in my area allows 1/2". But Hemp's book (awesome!) says
use 3/4", so thats what I went with.
As for winterizing, this is a year-around warm area, and it is even
allowed by code to run copper pipe along an outside wall. There is no
freeze protection anywhere, and the local big box stores do not even
sell freezeproof garden hose valves. Vacuum breakers are also not
spec'ed, so most stores do not sell them.
I will fill lots of pots full of water. The main shutoff at the street
works fine. I had to use it when I broke the PVC main a couple of
years ago while replacing a sprinkler gate valve connected to the PVC
pipe. It was kind of brittle. That's why I am afraid of the same
thing happening here. But there is one difference. The PVC in the
current case has a MIP adapter that I can easily get a wrench on. This
should relieve a lot of stress on the incoming pipe as I am removing
it. But there is little room for error.