If you live in a northern climate, you might be familiar with frozen pipes. But while most people worry about the kitchen sink or the basement bathroom, the humble is often the first to turn into an ice cube.
Unlike your kitchen sink, which usually drops straight down into a heated crawlspace or cabinet, a bathtub drain runs horizontally for a few feet before connecting to the vertical stack. Often, this horizontal run is located just a few inches below the floor—or worse, inside an uninsulated exterior wall or a poorly sealed subfloor. bathtub drain freezing
If you leave the house and the water continues to drip, that backed-up water can freeze in the tub itself. Ice expands. Expanding ice can crack porcelain or fiberglass. Suddenly, you aren't just dealing with a frozen drain; you are dealing with a cracked tub and a leak into the ceiling below. Do not pour boiling water directly into the tub. If the trap is frozen solid, the boiling water will sit on top of the ice, potentially cracking the porcelain due to thermal shock. If you live in a northern climate, you