Melt ice on steps without damaging concrete

How ice melt works, and how it hurts concrete

Ice melts work by dissolving into the ice and lowering the temperature at which water freezes, turning ice into slush you can shovel or that drains away. Common types include sodium chloride (rock salt), calcium chloride, magnesium chloride, potassium chloride and calcium magnesium acetate. Each works down to a different temperature: rock salt slows down a lot in hard cold, while calcium chloride keeps working at much lower temperatures. The bag lists the working temperature and the spreading rate.

Concrete is porous. Salty meltwater soaks into the surface, and when it refreezes, the expanding ice can pop off thin flakes, called scaling or spalling, especially on concrete that's young, poorly finished or not sealed. More freeze and thaw cycles mean more damage, and heavy use of salt means more water soaking in. Some deicers, especially products containing ammonium nitrate or ammonium sulfate, attack concrete chemically, and the Portland Cement Association advises against them. Metal tools used to chip ice also gouge and chip the surface. Using less product, choosing a gentler one, and sealing the concrete all reduce damage.

What damages concrete in winter

Let's fix it

1. Get ahead of the stormBefore snow starts, check that you have a plastic snow shovel, a push broom, an ice melt labeled safe for concrete and a bag of sand or traction grit. Some ice melts can be spread lightly before a storm to keep snow from bonding to the concrete, if the label says so; that uses less product than melting thick ice later. Mark the edges of steps and walkways if they're hard to see under snow. Make sure the outdoor light by the steps works, so you can see ice after dark.
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2. Shovel before it packs into iceClear snow as soon as you can, ideally before people walk on it and pack it into ice. Use a plastic shovel or a metal shovel with a plastic or rubber edge, and push snow off each step from the top down. Sweep the last thin layer off with a stiff broom. On steps, shovel the tread and push snow away from the house and the edges so meltwater doesn't run back onto the steps and refreeze. Lift with your legs, take breaks, and push rather than lift heavy, wet snow when you can. Shovel every few inches of snowfall during a long storm instead of waiting for the end, since 2 inches clears easily and 8 inches packed down does not.
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   Something went wrong?

   • There's a hard layer of ice under the snow Don't chip at it with a metal shovel or ice chopper, which gouges concrete. Spread a thin layer of ice melt, wait 15 to 30 minutes, and push off the loosened slush. Add sand for grip in the meantime.

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3. Spread ice melt sparinglyChoose a product labeled safe for concrete, and check its working temperature on the bag. Calcium magnesium acetate is the gentlest common choice for concrete, and calcium chloride works in colder weather, but any salt can add to flaking if overused; avoid products containing ammonium nitrate or ammonium sulfate. Spread a thin, even layer at the rate on the bag, often a small handful per square yard, using a cup or a handheld spreader rather than dumping it. Give it time to work, usually 15 to 30 minutes, then shovel off the slush. Don't keep adding more; extra melt mostly ends up soaking into the concrete or tracked indoors.
   Done

   Something went wrong?

   • Ice melt isn't working It may be too cold for that product. Check the bag's lowest working temperature, switch to calcium chloride for very cold days, and add sand for grip in the meantime.

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4. Add sand or grit for tractionSand, traction grit or non-clumping clay cat litter doesn't melt ice, but it makes it far less slippery right away, and it works at any temperature. Sprinkle it across the treads of each step and along the walkway, especially when it's too cold for ice melt to work or you want to use less melt. Many ice melts can be mixed with sand. Sweep sand up in the spring, or once the ice is gone, so it doesn't get tracked inside and scratch floors or wash into drains. A doormat inside the door catches what's left. Keep a small bucket of sand by the door all winter so you can grab a handful on the way out, before anyone has to step onto an icy tread.
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5. Protect new concreteConcrete is most vulnerable in its first winter, while it's still curing and before it's been sealed. The Portland Cement Association advises against using deicers on concrete in its first year. For new steps or a new walkway, shovel promptly and use sand or grit for traction instead of ice melt. Also avoid letting melt run off the driveway or roof onto new concrete. Once the concrete is a year old, applying a penetrating concrete sealer in dry fall weather helps it resist water and salt, following the sealer's instructions. If you aren't sure how old the concrete is, treat it as new for the winter.
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6. Sweep up leftovers and watch for damageOnce the ice is gone, sweep up leftover ice melt pellets and slush so they don't keep soaking into the concrete or get tracked inside. Look at the surface in spring. Thin flakes popping off the top, small pits or exposed gravel mean scaling. Light scaling can be cleaned and sealed to slow it down. Deeper damage or crumbling edges on steps can be patched; see how to patch a crack in concrete steps. Cracks large enough to make the steps uneven or wobbly are a trip hazard and need a contractor. Keep a note of which steps flaked, since those spots usually need the most care next winter.
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Watch it done

How to Safely Deal with Snow and Ice on Your Concrete!By Concrete with the Hauses on YouTube. Their method may vary a little from ours.

Watch on YouTube

If it comes back

If the same spot ices over every day, water is draining onto it. A downspout, roof edge or gutter that drips onto steps or a walkway is a common cause. Fix it once things thaw, and don't climb a ladder onto an icy roof or gutter; see how to clean gutters and how to prevent ice dams.

If an asphalt driveway is the problem, many ice melts are fine on asphalt, but cracks let water in. See how to fill asphalt driveway cracks before winter.

If salt keeps getting tracked inside, see how to remove salt stains from floors.