Fix those cracks before you break your mother’s back
A damaged concrete porch isn’t unheard of, especially if your home is more than a few decades old. However, what causes old concrete to crack, chip, or crumble can vary—and some situations may warrant swift and decisive action to prevent other, more expensive problems from happening. Here are eight ways to handle concrete porch repair, plus some preventive measures you can take in the future.
The most severe cause of a crumbling concrete porch typically concerns water leaking into the concrete. Concrete may appear strong and even dense, but it absorbs liquid quickly. When water and air bubbles get trapped in concrete, this can cause your porch steps to crumble, especially if you live in an area where the water trapped inside constantly freezes and thaws.
Common drainage issues that could be channeling water into your porch include:
Incorrect pitch of your yard
Clogged gutters or poorly laid gutter downspouts
Damaged roof
Incorrectly positioned drains
Left unchecked, drainage issues like the ones mentioned above could also lead to water into the foundation of your home. If it comes to that, fixing your porch may become the least of your problems. Check your drainage system first, then take swift action to resolve any issues causing your porch to break apart.
If your drainage system is intact and functioning as it should be, it could simply be an issue of wear and tear. Does your painted concrete porch get lots of foot traffic? Do your children like to play on it, or could animals (bugs or other critters) live under or on the sides?
If the structure appears unsafe, taper off the area and ask family members to use a different entry to your home until you fix the concrete.
A clean porch is a protected porch. While seeping water can build up inside of it, spraying it down with a power washer helps remove dirt and grime that could be causing the concrete to fall apart. Power washing your porch should be step one before you do any repairs. You might also want to take a scrub brush to remove any impurities the washer can’t get. In the future, try to clean your porch at least once a year.
Also, remember that you shouldn’t use a power washer if your concrete isn't sealed. To test if it’s sealed, see if water beads up on the surface of it. If it merely soaks into the concrete, it’s not sealed.
Instead, clean the concrete using a simple solution of 1 cup baking soda and 2 cups vinegar with a sponge or cleaning rag. The mixture will foam at first but can be used as a cleaning scrub agent to remove any dirt, grime, or bacteria buildup that could damage your porch in the future.
You should seal your concrete once every two to five years, depending on the harshness of your climate. Do so with a high-quality acrylic sealer. It’s easy to apply, affordable, and UV-resistant. If you don’t want a glossy finish, choose a penetrating sealer, such as a siloxane or silane sealer. These are mold-resistant and prevent freeze-thaw damage.
Also seal any holes or big chips, as they can reduce the tensile strength of the concrete holding your porch together. Sealing them off and reinforcing them prevents them from becoming more significant. You can also apply self-mixed cement or a vinyl patching mix to seal large holes. Or consider hiring a local concrete patio contractor to assess and repair your issue if it seems too big for a DIY project.
Note: Volatile organic compounds (VOCs) can be dangerous as they are highly flammable and can lead to short- and long-term adverse health effects, according to the U.S. Environmental Protection Agency. It’s important to wear a respirator approved for working with sealers containing high levels of VOCs. Apply them in a well-ventilated area and away from heat sources and open flames.
If your concrete porch is falling apart, you may need more significant concrete porch repair. You can use a smooth concrete dowel rod to reinforce significantly damaged portions of your porch.
The task can be labor-intensive, as it will likely require you to chip away at the crack or hole in your concrete to expand it wide enough to insert the steel dowel. At that point, you’ll need to drill the dowel into the concrete, fill it with replacement concrete, and seal it. But unless you’re a DIY expert, it’s best to outsource repairing a concrete porch to a pro with the right skills and tools.
Going forward, you’ll want to take some steps to prevent concrete porch issues from rising again. Assuming your drainage isn’t an issue, the main focus should be fixing hairline cracks or chips before they become bigger issues that require more expensive repairs.
Keep some putty filler or silicone caulk (both around $20) on hand to seal cracks. If your concrete isn’t sealed, it’s advisable to invest in this if you keep having to fix your porch. The same logic applies to protecting your garage floors as well.
Keep in mind that sealing concrete costs between $0.10 and $0.75 per square foot.
If your concrete porch has minor damage but a solid foundation, you can resurface your concrete, pouring a fresh layer on top. You can mimic your old design or decide to stamp, stencil, or color your concrete overlay.
Resurfacing your concrete porch involves repairing and cleaning the surface, applying a fresh layer of concrete on top, and adding a protective sealer. The cost to resurface concrete ranges from $3 to $9 per square foot.
It’s best to remove stains and rust from your concrete as soon as you notice them. You can apply a cleaning solution to the discolored spot (1/2 cup bleach per 1/2 gallon of water, 1 cup white vinegar per 1 cup of water, or 1/2 cup tri-sodium phosphate per 1/2 gallon of water). Let the solution sit for 15 minutes to break up the stain, then scrub with a stiff-bristled broom. Rinse the area with a pressure washer or garden hose with a spray nozzle.
If your porch has more significant concrete discoloration, apply a mild acid solution of 1% to 3% muriatic acid and water. Apply it to the area, let it sit for 5 minutes, scrub with a stiff-bristled broom, then rinse. Be sure to wear gloves when handling muriatic acid. If the acid comes in contact with your skin, rinse immediately to avoid skin reactions.
Consider using a commercial concrete cleaner if the stain doesn’t disappear with these household products. A concentrated alkaline soap in the cleaner can loosen the stain’s grip on your porch. Follow the manufacturer’s directions for removing the stain.
Cracking and crumbling concrete often stems from the installation process or a lack of maintenance. Prevent your concrete porch from damage by following these tips:
Cure the concrete properly during installation, following protocol for wet curing or another method. For instance, wetting the concrete 10 times daily for the first week ensures that the concrete hardens and cures to maximum strength.
Add control joints or steel reinforcement at installation or when the porch has structural damage.
Clean your porch with a pressure washer once a year to prevent grime, mold, and mildew.
Repair and seal concrete cracks, holes, and divots immediately.
Reseal your concrete porch every two to three years to help it withstand the elements and normal wear and tear.
Resurface the porch with a concrete overlay.
Drill small holes and inject expanding polymer foam below your concrete to lift sinking concrete.
Concrete porch repair costs around $3 to $9 per square foot, depending on the scope of the work. Replacing a concrete porch involves concrete demo costs (around $2 to $6 per square foot), plus the cost of a new concrete slab (around $4 to $8 per square foot). That means the total bill for a new concrete porch is anywhere from $6 to $14 per square foot.
If your porch has a few cracks or is crumbling in only a couple of areas, repairing the porch or resurfacing the concrete is the best route. If your porch is sloping, uneven, or in major disrepair, replacing it can make sense. Contact concrete contractors and get at least three quotes for your project.
Ben Kissam contributed to this piece.
Your porch could be crumbling due to poor installation, freeze and thaw cycles, or intense pressure washing or sandblasting. If your concrete was poured and cured improperly, moisture can seep into the concrete. When the water freezes and thaws, it causes stress to the structure, leading to cracks and crumbling. If you pressure wash concrete on too high of a setting or sandblast the surface, the concrete can also crumble.
The best way to resurface a concrete porch is to clean and prep the surface, pour a layer of concrete on top, allow it to cure, then seal it. A concrete overlay provides a durable layer and enhances your porch's look. You can even choose a stamped overlay to make it look like stone or brick. To ensure structural integrity, repair concrete cracks before applying the new concrete. If the existing concrete is in significant disrepair, consider removing and replacing the concrete instead of an overlay.
