A good rule of thumb is that Salt is for asphalt and Ice Melt is for concrete. There are different circumstances when you should use either one.
Things to consider:
- Salt (Sodium Chloride) is the cheapest and most affordable way to melt ice. It's about half the cost of most ice melt brands. You can even just use Solar Salt (the salt you use for soft water units). The Bad thing with salt is that it damages concrete, lawns, and plants.
- Ice Melt (Calcium Chloride) is about double the cost of rock salt. Some blends have Magnesium Chloride or Calcium and Magnesium. Either way they don't have the Sodium Chloride which causes damage to concrete. Ice Melt with Magnesium will melt at colder temperatures (as low as -25 degrees) and melts a little slower than Calcium does. But Calcium melts only as low as -15 degrees. There is also a misconception that ice melt won't hurt your lawn and plants. This is false. It has the same chemicals as your fertilizers but at a much higher concentration and therefore can burn up your lawn.
So to sum things up, use rock salt for asphalt areas, Ice Melt with Calcium and Magnesium (Roadrunner Brand) on concrete with temperatures as low as -15 degrees and for colder areas use Ice Melt with Magnesium (Sno-Plow Brand) on concrete with temperatures as low as -25 degrees.
