You know, up here I’ve noticed we can get down to around 19 or so if it’s for only one night without any problems with outdoor spigots and so forth. I do leave one tap with a slight dribble. Anything below that and I’ve always taken precautions. Or if it stays below freezing for even one 24 hour cycle you’d better drain and bundle things up. I rigged my heat tape up with switches this year so I don’t have to plug in and unplug constantly, because the auto cutoff is up around 45 and that’s too warm. Hundreds of watts gets expensive.
Are those pipes in a crawl space? My spigots come out of the basement and I’ve never done anything to protect them. They’ve survived many below zero nights with the lowest at -22. Over 30 years in this house.
Since 1 Oct we have hit about 19 a couple times momentarily. The rest of the time it has been bouncing around 10 to -20, and -30 in selected areas. It's -12 right now, but it doesn't feel a degree below -5.