What Is Safe to Put Down on Icy Concrete?

Rock Salt

• Common rock salt, or sodium chloride, is safe to use on concrete without any harmful effects. This relatively low-cost remedy is widely available at hardware stores, big-box retailers and home improvement stores. Rock salt comprises large salt crystals that melt ice in temperatures down to about 20 degrees. Their large diameter makes it difficult to cover an area completely however. Also, rock salt leaves a white residue on the concrete as well as on vehicles and can be tracked into buildings, causing stains.

Calcium Chloride

• Calcium chloride is a deicing salt formulated in small pellets that easily distribute to cover areas of concrete. This deicer, commonly marketed as ice melt in small bags, is effective down to 0 degrees. Consumers should be aware that calcium chloride is safe for concrete when used normally but can cause damage in large concentrated exposures. Spread calcium chloride thinly across an area, as it does not take much to melt the ice.

Magnesium Chloride

• Pelletized magnesium chloride, available in select markets of the United States, offers effective ice melting down below minus 13 degrees. Costlier than its alternatives, it offers superior ice melting performance. Magnesium chloride also causes less harm to plants and ground water than other deicing salts, as it releases lower levels of chlorides. Moreover, it does not leave a white residue when tracked onto a flooring surface or on vehicles.

Sand

• Sand can be mixed with an ice melt or used alone to add grit to the ice, allowing for greater traction. Sand works best when temperatures are at freezing or higher during the daylight hours, allowing the ice melt slightly. The sand placed upon the melting ice will act as a traction device when the ice refreezes at night. Do not place sand on ice during below-freezing temperatures without an ice-melting agent, as it can increase the slipperiness of the ice.