These tend to have the "wedge" freeze up and then the valve breaks in the closed position when you try to open it.

Also how do you keep your out door water hydrant from freezing in the winter in the crawl space?

I have monitoring during renovation and when occupied by renters for Burgulary, Fire, Freeze, Carbon Monoxide, Water Leaks, and Gas Leak.  

Maryland weather is unpredictable this time of year...it was 70 degrees on Christmas, but will be below freezing at night this week.

I've always liked the idea of piers vs. traditional foundations they seem more forgiving and I suppose you don't have much of a freeze/thaw problem in your area.

Finally, you should install a drain, or better yet a sharkbite connector, just inside the main shutoff valve, so that you can easily drain the water from all the water lines during the winter (so that no lines will freeze).

I used to go winter camping in the mountains, in temps way below freezing.

Credit freeze is cheap insurance.

(though when the high is below freezing, its still cold!)

In the winter, freezing cold air can enter into your home, making your floors and air in your home cold which will cost you more in higher heating costs.