Here are some additional conditions that should be reviewed around ANY home when the weather gets very cold, as was the case recently.
Ensure all gaps and openings in the basement or crawlspace walls are filled. The smallest amount of wind on very cold days (anything below 15F) will penetrate these gaps. If pipes are nearby these gaps, it takes very little to freeze them. In this case, close the crawlspace vents to prevent cross ventilation. Be sure to open them after the weather moderates.
Gaps in siding walls create the same problem. Extremely cold temperatures and high winds do some unbelievable things related to freezing. I have seen pipes on interior walls actually freeze if there was an opening of the smallest type to the outside that would allow cold air to reach the pipes, especially if it was on the windward side of the home. Seal even the smallest gaps to prevent this. I grew up in lots of -20F winters. As I look back, since it has been a while since we have seen these temperatures, it still amazes me how some pipes could freeze where they were located.
This information was originally published at http://ishopgreenwood.com/2009/01/20/jims-frozen-pipe-follow-up/