Preventing frozen pipes starts with preparation. Disconnect and drain outdoor hoses to prevent water from freezing and backing up into the pipes. Insulate exposed pipes with foam sleeves or heat tape, and seal any air leaks near pipes, vents, or crawlspace doors to block cold drafts. Open cabinet doors to allow warm air to circulate around pipes under sinks, especially those along exterior walls. Keep your thermostat set to at least 55°F, even when you're away, to maintain a safe temperature for your pipes.