[LazyPup]

Sometimes a fully finished basement can introduce a problem. Once the basement ceiling is closed in it prevents residual heat from the basement from getting into the space between the basement ceiling and upper subfloor. That can then be compounded by minor air gaps in the sill plate on the top of the footer wall. Cold air gets into the space and is trapped in there. If the basement ceiling is attached directly to the bottom of the floor joists there is not much you can do, however, if the basement ceiling is even slightly suspended below the joists you may want to consider installing a couple grilles to allow some of the heated air from the basement to rise into the cavity between ceiling and floor. That would not only help protect the piping but it would also help keep the upper floors from being so cold.

As for you frozen water line, you might try leaving a faucett in the basement bathroom slightly open. That way as the pipe warms up even slightly during the day it would allow the water to flow, which will aid in thawing the pipe. Once even the slightest flow begins the ice should thaw relatively quickly.

A word of caution here though. You definitely want to keep a close eye on it because the pipe could have burst from freezing. If that is so, it will leak immediately after thawing begins. You will then have to valve that section off at a zone valve or shut it off at the main until the ruptured pipe can be repaired.