Re: EXTREME freezing temperatures - What to worry about?
Leave the doors open to any rooms with pipes so heat can get in, leave the doors open under the sinks as well.
If you have a basement door and have heat in the basement turned on close the door or all your heat will just bleed up stairs.
Frozen pipes won't explode if the ice has someplace to go. If the pipe is frozen leave the taps turned on this allows the air to escape and the ice can expand up the pipe rather then blow the pipe. Also it's possible leaving the tap open will allow warmer air into the pipe and unfreeze. If the hot and cold pipes are close together in the wall run the hot water and it may warm up the inside of the wall enough to get the cold water going again.