How Long Springs Last, County by County
The same 10,000-cycle torsion spring retires on very different calendars in Duluth and San Diego. This index turns NOAA county climate normals into honest spring-life bands for all 668 covered counties — the model behind every city page on this site, published with its data for anyone to check, cite or reuse.
The national spread, in four numbers
The five climate bands, and what they do to steel
| Band | Climate | Modelled spring life* | Covered counties |
|---|---|---|---|
| Severe | the hardest freeze climates — deepest HDD loads, earliest failures | 6–9 years | 164 |
| Cold | real winters with sustained freeze-thaw cycling | 7–11 years | 203 |
| Moderate | seasonal cold without the deep-winter grind | 9–12 years | 153 |
| Mild | light winters — cycle count dominates over climate | 10–13 years | 120 |
| Minimal | effectively frost-free — the top of the national range | 11–15 years | 28 |
The extremes of the covered map
Hardest counties on spring steel
| County | HDD | Modelled life |
|---|---|---|
| Clear Creek County, CO | 9,929 | 7–9 yrs |
| Summit County, UT | 9,362 | 7–9 yrs |
| Forest County, WI | 9,160 | 7–9 yrs |
| Teller County, CO | 8,900 | 7–9 yrs |
| Pine County, MN | 8,813 | 7–9 yrs |
| Hamilton County, NY | 8,737 | 7–9 yrs |
| Kanabec County, MN | 8,619 | 7–9 yrs |
| Mille Lacs County, MN | 8,605 | 7–9 yrs |
| Wasatch County, UT | 8,575 | 7–9 yrs |
| Barron County, WI | 8,574 | 7–9 yrs |
Easiest counties — springs die of cycles, not weather
| County | HDD | Modelled life |
|---|---|---|
| Monroe County, FL | 179 | 11–15 yrs |
| Miami-Dade County, FL | 184 | 11–15 yrs |
| Broward County, FL | 225 | 11–15 yrs |
| Collier County, FL | 287 | 11–15 yrs |
| Palm Beach County, FL | 297 | 11–15 yrs |
| Lee County, FL | 363 | 11–15 yrs |
| Martin County, FL | 365 | 11–15 yrs |
| St. Lucie County, FL | 440 | 11–15 yrs |
| Charlotte County, FL | 448 | 11–15 yrs |
| Sarasota County, FL | 518 | 11–15 yrs |
Take the data
Download the county-level CSV
668 rows: county FIPS, name, state, annual heating degree days (1991–2020 normals), climate band, and the modelled spring-life range. Free to reuse with attribution (CC BY 4.0); regenerated from source data on every site update.
Methodology, honestly stated
Torsion springs fail by metal fatigue — cycle count — with climate as the modifier: cold stiffens steel, propagates micro-cracks on hard-freeze mornings, and concentrates failures into winter. The model starts from the industry-standard 10,000-cycle rating at typical household usage and adjusts the band by each county's NOAA heating-degree-day normal. It is a planning estimate, not a warranty: heavy daily usage shortens any band, high-cycle springs stretch it, and coastal salt air ages hardware on its own schedule regardless of temperature.