I live in a house that was built in 66, it's on a slab (no crawl space
or basement), and it's all copper or galvanized pipe.

I live in Southern Virginia, and it's been freezing lately. We haven't
had any problem with our pipes yet - but a neighbor did. Their
interior pipes burst, but no one was living in the home at the time
(it's for sale) and the heat was off. so that may have factored into
it.

I'm wondering if I have to worry about my pipes freezing below the
slab/under the house. There is also one copper pipe that sticks out
from the foundation about 5 inches. It leads out to some buried pvc
pipe to carry water to the other side of the yard. I have that shut
off (no water going out to the pvc). but i'm worried that the 5 inches
that is exposed just before the shut off valve is in danger.

i'm sure i'm going to get a ton of opinions on this... my girlfriend
thinks letting the water trickle from a faucet in the house is a
waste. she just assumes turning off the water to the house at the
street.

Any thoughts on this would be great. Thanks everyone.