I know of a house where one side of the structure's plumbing gets frozen any time it's 20 degrees for 2 days. How to prevent this? Have plumbing in the interior and not running through outer walls?
How about the garden hose on the outside? Maybe have a shutoff valve?
If the pipes are all in heated space...and the heating system doesn't fail, no frozen pipes. As to the hose bib, all you need is a properly installed frost-free hose bib. The working guts are inside heated space (a long shaft on the handle allows the actual shutoff to be way inside). Many of these only can work if you remember to remove the hose, otherwise, it can trap water instead of draining, so, water, cold = freezing. there are some that will drain regardless of whether you have a hose left on (check out www.woodfordmfg.com for some of the better ones). If pipes are on an outside wall, sealing for air leaks is critical. If there are no air leaks and the pipe is close to the interior, heated space, then it may not freeze. Bad place is say under a kitchen cabinet. With the cabinet doors closed, no air movement, it can get quite cold in there, especially if you didn't air leak seal things up well.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013