Can Ice Melt Damage Sidewalks?

Significance

• The three most common ice melt ingredients chemically attack concrete. They are ammonium sulfate, magnesium chloride and calcium chloride. However, most of the damage to sidewalks comes from a process called the freeze-thaw cycle, rather than from ice melt chemicals.

Freeze-Thaw Cycle

• During the freeze-thaw cycle, moisture seeps into sidewalk cracks and surface pores and then freezes. When the moisture changes into ice, it expands, putting pressure on surfaces. The chemicals in ice melt products actually increase the number of times the freeze-thaw cycles occurs, in effect doubling the rate of expansion during freezing.

Considerations

• Weak pavements and concrete that is less than one year old are at greatest risk of damage. Masonry, stone and asphalt are also susceptible to the freeze-thaw cycle. You can protect these surfaces by using a pure traction aid, such as garnet sand, instead of harsh ice-melting chemicals.

Benefits

• Ice-melting products are best applied before a freeze, but a freeze cannot always be anticipated. If possible, apply a sealant before cold weather to prevent damage to a sidewalk.

Warning

• If keeping a sidewalk clear is critical, as in a high-traffic area, risking damage to the sidewalk by using ice melt far outweighs the potential liability and injuries from falls or accidents.

Insight

• Ice melt is more likely to damage indoor floors and surfaces than outdoor sidewalks and walkways. Clean up deicers put down outside, and use a track mat to help prevent damage.