My plumbing friend told me a sad story today about a young couple and their family that just returned home from a fantastic holiday to Disneyland. Their furnace had quit during their holiday, and because no one was checking on the home, all water pipes froze and burst. The toilets froze, the pea traps and drains froze, even their main drain in the home froze. The basement walls had in some places up to a 4" thick layer of frozen water from the rim joists down to the basement floor. Every wall in the home that had a water line or pipe running through it was damaged, and will need replacement. All plumbing pipes, water lines, and toilets will need replacing. Such a sad ending to a magical holiday.
So, what do we learn from this tragedy? If you go away, even for a few days, have a family member or a neighbour stop by and check on the home. A quick but thorough walk through every couple of days should be all that is needed. Check with your insurance company to determine the exact amount of checks needed. Another action that would have limited the amount of damage done would have been to turn off the main water supply valve before leaving, a good practice to get into.