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Pounds and bags of rock salt or calcium chloride for your driveway and walks, by pavement temperature.
With these inputs:
| Result | Value |
|---|---|
| Ice melt for the winter | 23 – 45 lb |
| First application | 2.3 – 4.5 lb |
| Per storm (1 application) | 2.3 – 4.5 lb |
| 50 lb bags | 1 |
| Area | 1,000 sq ft |
| Rock salt (sodium chloride) at 23 to 28 °F | 2.3–4.5 lb per 1,000 sq ft |
| Later passes | ½ to the full first rate |
Shovel or plow first — de-icer only breaks the bond between ice and pavement. Leave space between granules and sweep up what's left after the storm. On a gravel driveway skip the salt — it speeds the breakdown of limestone; sand or grit gives traction.
Most people spread far more salt than ice needs. This calculator uses the Wisconsin Salt Wise application chart (Dane County LWRD): rock salt at 2.3 lb per 1,000 sq ft near freezing and up to 6.8 lb at 15–23 °F; calcium or magnesium chloride from 0 °F down to −5 °F. Enter the paved area, product and pavement temperature for pounds per storm, per season and bags to buy.
Wisconsin Salt Wise's de-icing chart (Dane County LWRD) gives rock salt at 2.3 lb per 1,000 sq ft at 28–32 °F, 2.3–4.5 lb at 23–28 °F and 2.3–6.8 lb at 15–23 °F. That is far less than most people spread.
Below 15 °F the chart does not recommend dry rock salt — it melts slowly and leads to over-application. Calcium or magnesium chloride is rated at 2.3–6.8 lb per 1,000 sq ft from 0 to 15 °F and 6.8 lb from −5 to 0 °F. Below −5 °F the guidance is to plow only and use sand for traction.
Measure the paved area: a 20 × 50 ft driveway is 1,000 sq ft, so 2.3–4.5 lb of rock salt per application at 23–28 °F. Ten storms at that rate use 23–45 lb — a single 50 lb bag.
Yes. Remove as much snow and ice as possible first; de-icer is meant to break the bond between ice and pavement, not melt all the snow. For later passes in the same storm, use half to the full initial rate.
Over-application is the main harm: salt that is never used washes into lawns, soil and streams. Sweep up leftover granules, keep new concrete (under a year old) free of de-icers where the manufacturer advises, and rinse pets' paws after walks.
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