Pipe Freeze Risk Checker
Answer four questions about one pipe, or one part of your house, and get a low, moderate or high rating with plain steps to take. It is a quick sorting tool. It does not know your house, so use the result as a prompt to go and look.
How the score works
Each answer adds or removes points, and the total sets the rating. There is no hidden formula. Everything the checker uses is in this table, and the result box shows the points it gave you.
| Question | Answer | Points |
|---|---|---|
| Outdoor temperature | 33°F or above | 0 |
| 25 to 32°F | 1 | |
| 20 to 24°F | 2 | |
| 10 to 19°F | 3 | |
| Below 10°F | 4 | |
| Where the pipe runs | Interior wall or heated space | 0 |
| Exterior wall or attic | 2 | |
| Crawlspace | 3 | |
| Insulation on the pipe | Yes (only counts outside heated spaces) | minus 1 |
| No | 0 | |
| Heat in the space | On | 0 |
| Off | 3 |
Why these four questions
Temperature matters because water starts to freeze at 32°F, and trouble for exposed lines is commonly cited around 20°F and below when the cold lasts for hours. Location matters because a pipe in a crawlspace or an outside wall has little between it and the cold, while a pipe in a heated room has a lot. Insulation slows heat loss from the pipe. Heat is the largest single factor, so it carries the most points when it is off.
What the result cannot tell you
It does not know how long the cold will last, because a few hours below freezing is a different problem from three nights. It does not know about wind, which pulls heat off a pipe quickly, or about gaps where outside air reaches a line. It does not know if the pipe has frozen before, or what it is made of. Treat a low rating as permission to relax, and a high one as a reason to act today, not as a measurement.
One more limit: the checker rates a single pipe at a single moment. A house has many pipes, and the weakest one decides the outcome. If you are checking before a cold snap, run it once for each exposed spot, such as the crawlspace, the sink on the north wall and the garage line, and act on the highest result.
If a pipe freezes anyway
Open the faucet so melting water has a path out, warm the pipe slowly with a hair dryer, and shut off the main if you see water or a split. After a break, see frozen and burst pipe cleanup. The post on keeping pipes from freezing has a timeline for the two days before a hard freeze. If water is already running, call (301) 786-0888.