Upstairs Bathtub Faucet Won't Run or Drain

[Briansnorthstar]

I come from the north but now live in the south. One of the BIG rules of plumbing in the north is that you DO NOT run plumbing in an outside wall! Here in the south I see it all the time. Code says protect from freezing my thought is that unless you live in an area that NEVER gets below freezing do not run plumbing in an outside wall and if over an unheated space such as a garage INSULATE INSULATE INSULATE!!!