Using Ice Melt on Concrete
Safety and ease of access are primary considerations when using ice melt on
sidewalks, driveways, and roads. Ice melt can be used for many years with no
damage on good quality concrete. But under extreme conditions, concrete
damage can occur with any ice melt.
Concrete damage is caused by weak melt brine going into the pores of the concrete, refreezing and expanding and creating small fissures. Each freeze/thaw cycle causes just a tiny bit more crack until a piece flakes off, which is called spalling, a severe form of scaling. Refer to The Portland Concrete Association’s document “Concrete Slab Surface Defects: Causes, Prevention, and Repair.” https://www.cement.org/docs/default-source/fc_concrete_technology/durability/is177-concrete-slab-surface-defects-causes-prevention-repair.pdf
To minimize damage, we recommend removing the ice and ice melt after it has done its job and broken up the ice. Leaving ice melt on the concrete or sprinkling ice melt back onto the cleared concrete increases the risk of spalling. Where that granule sits, the freeze / thaw cycle continues repeatedly, even with small amounts of water. That is why the concrete often looks “pocked.” Those little craters are often where a piece of ice melt sat for days.
Consumers may have used a deicer product for years with no problem. Then suddenly, something is different, and damage occurs. The product is not different. We use the same products and blends we have provided our customers for many years. It is the weather that is different – extreme conditions contribute to multiple, damaging freeze / thaw cycles.
Resurfacing and sealing can fix and prevent damage in the future. Several good concrete repair and prevention products are available. Read the packaging and make sure you use it as recommended – both application instructions and frequency.
The products that have the very least likelihood of damage are acetates (like CMA - calcium magnesium acetate), which are gentler, but tend to melt slower and often to only about +10 degrees F, depending on the product. Acetates are premium products and we sell them in our Viper line. Some companies blend small amounts of CMA or other acetates into regular ice melt, but small amounts don’t really make a difference. At least 20% is required to affect the corrosion potential of the product.
Balancing safety and ease of access is challenging in climates where brutal weather can challenge any product. Understanding the product and how to use it safely and correctly can help extend the life and appearance of your concrete for many years.