Why Pipes Burst in Places That Rarely Freeze
A few hard nights a year
762 counties get between a trace and ten nights a year below 20°F, the point where a bare pipe in a garage, attic or outside wall starts to freeze. That is 24% of the country. The states with the most of them: TX (176), GA (142), MS (66), LA (63), NC (51), AL (47). In Minnesota builders keep pipes out of attics and outside walls. In Texas and Georgia it is common, because the cold that would freeze them comes a few nights a year, or skips a year entirely.
A few nights a year, in real places
| County | Below 32°F | Below 20°F | Below 10°F |
|---|---|---|---|
| Harris County, TX | 7 nights | under 1 night | none |
| Dallas County, TX | 28 nights | 2 nights | under 1 night |
| Travis County, TX | 30 nights | 1 night | none |
| Fulton County, GA | 53 nights | 5 nights | under 1 night |
| Mecklenburg County, NC | 60 nights | 8 nights | under 1 night |
| Shelby County, TN | 61 nights | 10 nights | 1 night |
| Orleans Parish, LA | 4 nights | under 1 night | none |
"Under 1 night" is an average. In practice it means most winters pass with none, and then one week brings several in a row - the pattern of the February 2021 freeze across Texas, when pipes burst in houses that had never needed protecting before.
Why the rare freeze hurts more
Three things stack up. Pipes run through unheated attics and outside walls with little or no insulation. Outdoor spigots are not frost-free. And nobody has a night-of routine, because they have never needed one. A county with 60 hard nights a year has houses built for all 60. A county with two has houses built for none.
What to do if you live in one
You do not need heat tape on every run. You need two things: foam sleeves on any pipe you can reach in the attic, garage or crawlspace (an afternoon and a few dollars a length), and the night-of routine on the nights the forecast drops below 20°F - drip the taps on outside walls, open the sink cabinets, unhook hoses, keep the heat at 55°F or above. Know where your main shutoff is before the night comes, not after.
Where to go next
See the range: Hennepin County, MN, Cook County, IL, Harris County, TX, Miami-Dade County, FL.
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