Most homeowners reach for rock salt to clear their driveways and sidewalks during winter. It’s economical and reliable, and it easily melts ice in temperatures as low as 5 degrees Fahrenheit to keep driveways and sidewalks clear and safe.
But when the temperature dips lower, salt alternatives such as magnesium chloride or calcium chloride offer increased melting power. Of the two, magnesium chloride is a better choice for homeowners, according to Jerry Poe, technical director for North American Salt Company.
“Both magnesium chloride and calcium chloride are fast-acting and melt ice and snow at extremely low temperatures compared with rock salt and other salt alternatives and blends,” says Poe. “But because magnesium chloride is nontoxic, it is safer for homeowners, their pets and their property, so it ultimately provides a better value for the dollar. It’s tough on ice and snow, but safe on everything else.”
The chemical makeup of pure calcium chloride can burn skin, so it requires homeowners to wear goggles and gloves when applying it. It can also burn pets’ paws and draw moisture from plant roots, effectively dehydrating vegetation.
Magnesium chloride, on the other hand, is naturally extracted from sea water or brine, produced through solar evaporation, which is an environmentally friendly process. Its chemical makeup is much gentler than calcium chloride – in fact, it’s less toxic than baking soda – so it is safe for homeowners to handle.
Magnesium chloride is also safer for pets because it doesn’t burn paws that have been cracked in cold temperatures, and it is less likely to clump between a pet’s paw pads. And, it is gentler on grass and plants, so homeowners who use magnesium chloride products and follow application instructions are less likely to have to repair or replace landscaping in the spring.
Concrete maintenance can also be an issue for homeowners who live in colder climates. “Many people think that ice melt products cause damage to concrete, but the real culprit is the freeze/thaw cycle,” says Poe. “When ice melts, the resulting liquid works its way into cracks in the concrete. When the liquid refreezes, it expands and causes further cracking or spalling.”
The solution? After using an ice melt product, Poe recommends removing the resulting slush and brine before it has a chance to refreeze. Opting for magnesium chloride rather than calcium chloride will further prevent concrete damage.
“A recent study at Purdue University revealed that concrete treated with calcium chloride deteriorated two times faster than concrete treated with magnesium chloride. The calcium chloride chemically attacks concrete, even before freeze/thaw cycles take place,” says Poe.
While magnesium chloride used to be available only to ice control professionals, today it is available to homeowners in several forms. For example, the Safe Step line of packaged deicers offers a 100 percent magnesium chloride product as well as several ice melt blends that contain the ingredient.
When evaluating different ice melt products, check the packaging to see if magnesium chloride is part of the product formula, and whether the product is labeled as safe for people, plants and pets. A bit of education and planning before the first storm hits can help you have a safe and enjoyable winter, even when temperatures plummet.