How do I keep concrete steps from crumbling?

Concrete steps crumble when water soaks in and freezes, again and again, and salt makes that cycle worse. So the whole job of keeping steps sound is keeping water and salt out of the concrete: go easy on deicers and choose the right ones, keep roof water off the steps, seal them with a breathable sealer, and patch small damage before winter gets into it. None of it takes more than a few hours a year.

Why steps crumble

Winter freeze/thaw cycles are what damage outdoor concrete, which is why Quikrete advises assessing the damage each early spring.^[4] Water gets into the surface, freezes and flakes the top off a tread or the edge of a step. Salt makes it worse: the Town of Berryville warns that treating with salt and other deicers can lead to chips and cracks, discoloration, and surface weakening.^[1] Steps take more punishment than flat concrete: water runs over every edge, snow gets packed down on the treads, and they get more salt than any other surface around the house.

Choose and use deicers carefully

Use less of it. Shovel first, then use just enough to break the bond between ice and concrete. A deicer only needs to loosen the ice so you can clear it, not melt the whole layer. Sand does not melt ice but gives traction.

Read the label. In Virginia, deicers with fertilizer ingredients are not sold for paved surfaces: since December 31, 2013, it is unlawful for any person to offer for sale any deicing agent containing urea or other forms of nitrogen or phosphorus^[2] for use on sidewalks and other paved surfaces.

Treat new steps differently for a year

New concrete is the most vulnerable. The Town of Berryville tells residents that concrete has a curing period of approximately a year, during which it is highly susceptible to damage from deicers,^[1] and suggests sand, sawdust, clean kitty litter, and birdseed^[1] for traction instead of salt. It also notes that damage resulting from the application of deicers is not generally eligible for warranty repair or replacement,^[1] so ask your contractor what their warranty says about salt before the first snow.

Keep water off and away

Don't let salty water sit. Sweep slush off the steps after a storm rather than letting it refreeze in place.

Fix the gutters and downspouts. A downspout that dumps onto the steps or the walk below them soaks the concrete every time it rains. The Northern Virginia Soil and Water Conservation District says gutters should be cleaned free of debris at least once a year,^[6] more often under trees. Extend any downspout that empties next to the steps.

Seal the joint at the house. The joint between the top step and the wall should hold a flexible sealant, which Quikrete says is there to prevent water from penetrating the joint and deteriorating the sub-base.^[5] If the gap is widening, read why concrete steps pull away from the house before you seal it.

Seal the steps

A penetrating silane-siloxane sealer helps keep water and salt out of the surface without leaving a film. It works only on clean, dry, bare concrete that is still porous, and it goes on in mild, dry weather. Patch any damage first rather than sealing over flaking concrete.

As an example of what to look for, Quikrete's Concrete & Masonry Waterproofing Sealer is a water-based, silane-siloxane formulation,^[3] and its data sheet says it resists water, deicing salts, and gasoline.^[3] Its instructions are typical of the type:

• On new steps, allow a minimum of 30 days for new concrete to cure before applying it.^[3]
• To check older steps, place drops of water on the surface; if the water is absorbed, the surface is porous enough to accept the sealer.^[3]
• Apply to clean, bare concrete, not over existing paint or stain.^[3]
• Apply only when air and surface temperatures are 50 F to 90 F, and not if rain, heavy dew or temperatures below 50 F are expected within 24 hours.^[3]
• For quantity, one gallon covers approximately 75 to 150 square feet,^[3] depending on how porous the concrete is, so measure the treads and risers before you buy.

The same water-drop test tells you when to reseal: when water stops beading and starts soaking in, the steps are ready for another coat. How often concrete should be sealed goes into more detail.

Catch small damage early

Quikrete's repair guide says to inspect your concrete and masonry walls, walks and slabs for damage on a regular basis, and that early spring is an excellent time to assess any damage from winter freeze/thaw cycles.^[4] A chipped nosing or a small flaking patch lets water in and grows each winter; fixed in spring, it is an hour's job. How to fix crumbling concrete steps covers the repair.

If you are replacing the steps

Durability is mostly decided on the day the concrete is poured. Ask your contractor to put the mix, the air entrainment, the curing method and any winter protection in the quote, and ask what the warranty says about salt; what concrete steps cost in Virginia lists the other things to ask about.

Stop and call a pro if

• The flaking is deep or covers most of the treads despite patching and sealing.
• A step is cracked through, rocking or sinking.
• The steps are pulling away from the house and the gap keeps growing.
• You see rust stains or exposed steel in the broken concrete.
• Water is getting into the basement behind or under the steps.

Getting help in Virginia

Loclis lists DPOR-licensed concrete businesses with their licence number and class. Look up concrete contractors in Blacksburg, browse sealing and resurfacing or sidewalk and step contractors, or see all concrete and hardscaping answers.

Describe your steps once and licensed local concrete businesses quote the work.