Winter
Which ice melt does the least damage to asphalt and concrete?
Ice melt damages pavement through the meltwater it makes rather than chemically, so the less of it that clears the ice, the less the surface takes.
The numbers
- The damage is freeze and thaw, not corrosion. Meltwater soaks in and refreezes.
- More product on the ground means more meltwater, whichever bag it came out of.
- Every ice melt has a working temperature range on its own label, and below that range it does little.
- Follow the manufacturer's label for the product, the spread rate and the temperature.
- Sand melts nothing. It adds grit, and it has to be swept up before it reaches the drains.
- New concrete: industry guidance is to keep deicing chemicals off it through its first winter.
What does the damage
Ice melt works by melting ice. The meltwater soaks into whatever is under it and refreezes when the temperature drops back, and that cycle is what takes a surface apart. So the amount on the ground matters more than which bag it came out of.
The usual mistake is a heavy spread on a night far colder than the product works at. It sits there doing almost nothing, gets tracked indoors, runs into the grass, and does its melting on the one warm afternoon when it can do the most harm.
What the label tells you
Every ice melt sold carries its working temperature range, its spread rate and its handling directions on its own label, and those differ between products and between formulations of the same product. The label is the instruction that applies to the bag in your hand.
Naming one here would be a recommendation about a chemical going onto your property, around your landscaping and around whoever walks on it, made by somebody who has not read that label or seen your surface. What is worth saying is the part that holds for all of them: use the least that clears the ice, and sweep up what is left.
What asphalt and concrete each mind
Asphalt takes the freeze and thaw. Every extra cycle works on every crack that is not filled, which is why a surface that was crack filled and sealed before winter comes through in better shape than one that was not.
Concrete is the one to be careful with, and new concrete most of all. The concrete industry's own guidance is to keep deicing chemicals off a slab through its first winter, while it is still gaining strength and its finished surface is still vulnerable.
The part that is not the chemical
Sand does not melt anything. It gives grit on top of the ice, and it ends up somewhere: on a commercial property that somewhere is usually the catch basins, which makes it a spring cleaning job and a drainage problem when it gets skipped.
If a lot takes winter badly year after year, the ice melt is rarely the whole story. Where water collects, where it drains to and which cracks are open decide most of it, and that is worth having somebody look at before the next season rather than after it.
Where these numbers come from
- Working temperature ranges, spread rates and handling directions are on each ice melt manufacturer's own product label.
- Keeping deicing chemicals off a slab through its first winter follows American Concrete Institute and Portland Cement Association guidance.