Larry, see my post below. It all depends on your history. I've live in houses with crawl spaces, one with copper, one with pvc and they froze on occasion if I was dripping the water. As soon as I went to a pencil stream inside and out no more problem. I figure overkill is better than sorry. But if you are brick, well insulated, and run the faucet closest to the junction with the outside faucet, and it's wrapped, you can skate....until it freezes, lol. Another thing to do is buy your plumbing supplies ahead of time, like in the summer, lol, because when your pipes freeze, and lot of other ones did too, and they beat you to home depot, lol. I have several cans of glue, cleaner, and lots of hot and cold pipe on hand in case I mess up. That Feb a few years back where it stayed below freezing for days, I waited until about four that first cold day to run the water, and it was already too late. Now I start running it hours before it hits freezing, because I was under the house in the dark fixing them when they broke after it went above freezing, and I was cussing, and fuming, and made myself a promise, "Tony, you damn idiot, run the damn water, if froze once, it will do it again", lol.
