Was -30-C here last night, -31C for tonight (-42C W/ windchill).
I don't turn water off or do anything.
But if you are worried about it, instead of turning water off, it's likely better to open a faucet some place and leave it open a little more than a drip (thin steady stream).
What sucks more is when the dog wants to go out and pee and I open that door. bRrRrRrR
Congrats on being home alone!
Make the most of it.
Pizza and beer
Call in sick tomorrow
Eat more pizza and have more beer
Because in a few day you are likely going to have 10-inches of snow that will need shoveling while it's -25 out
...And that will be one miserable little nippley job