Frozen — Drain Pipes [patched]

Drains contain standing water in traps (P-traps, drum traps) and low spots. When that water freezes, it expands and seals the pipe. Common culprits: uninsulated pipes in crawl spaces, exterior walls, unheated garages, or basements. Kitchen drains are especially vulnerable because grease deposits trap water and freeze at higher temperatures.

Here’s a complete, practical piece on —covering causes, signs, solutions, and prevention. Frozen Drain Pipes: Causes, Warning Signs, and How to Fix Them frozen drain pipes

When temperatures plummet, most homeowners worry about frozen water supply pipes. But frozen drain pipes can be just as troublesome—and often catch people off guard. Unlike supply lines, drains aren’t under pressure, so a freeze doesn’t cause bursts as dramatically. Instead, it creates a solid blockage that can lead to messy backups and slow disasters. Drains contain standing water in traps (P-traps, drum