Not every damaged slab needs to come out. Safe Concrete looks at the cause of the damage first, then recommends repair, leveling, resurfacing, sealing or replacement.
Concrete damage has a handful of common causes: shrinkage, settlement, water, freezing, chemicals and traffic. The right repair depends on which one you have. Filling a crack that is caused by a sinking slab is a temporary fix, and sealing a surface that is scaling because of a poor mix only delays the problem.
When you send photos and a description, we will ask when the damage appeared, whether it is changing and where water goes around the slab. Those answers separate cosmetic wear from problems that need a structural or base fix.
Slab leveling pumps material through small holes drilled in the slab to fill voids and lift the concrete back toward its original height. Traditional mudjacking uses a cement-and-soil slurry, while polyjacking, also called foam leveling, uses an expanding polyurethane foam. Both go after the same problem, the empty space where soil has washed or compacted away.
The methods differ in hole size, materials, weight, cure time and cost, and neither is the right choice for every slab. Our guide on mudjacking vs polyjacking sets out the differences. Leveling only works if the cause of the settlement is addressed, so we will ask about drainage, downspouts and tree roots.
A sealer slows water, stains and salt from getting into the surface. Penetrating sealers soak in and leave a natural look, while film-forming sealers sit on top and can add sheen or deepen color. The choice depends on the slab, the finish, the climate and how the surface is used.
Preparation determines the result. The surface needs to be clean, free of old coatings and stains, and dry. The process is covered step by step in how to seal a concrete driveway.
Sometimes repair is a poor use of money. A slab with widespread cracking, a failed base, major heaving or a surface scaling across its entire area may not hold a repair for long. In those cases we will say so and talk through replacement, covered on our concrete driveways page for driveways and the patio and walkway pages for other flatwork.
We would rather tell you a repair is not worth it than sell you one that fails by next winter.
A sound repair plan describes the cause of the damage, the method, the materials and what you should expect afterward. It also tells you what the repair will not do. A crack filler will not make a slab look new, leveling will not fix a failing base elsewhere in the slab, and a sealer will not rescue concrete that is already breaking down.
We also talk through timing. Repairs need dry weather and proper curing time, patches have temperature limits, and sealers need a clean, dry surface. Scheduling around the season, and being honest about what is realistic in cold or wet weather, is part of doing the job properly. Ask for the plan in writing before you approve any work.
Take pictures in daylight from a few feet away and from standing height, and place a coin or tape measure next to cracks for scale. Note where the downspouts, trees and low spots are. If the problem is a trip hazard, mention how large the height difference is, since that affects whether it is a quick fix.
Narrow, stable cracks can often be sealed or filled. A crack that is wide, growing, or has one side higher than the other is moving, and filling it alone will not last. The cause needs to be found first.
It can hold well when the cause of the settlement is resolved. If water keeps washing soil out from under the slab, new voids can form. Drainage fixes are part of a durable repair.
Wait until it has cured and any curing compound or residue is dealt with. A common general guideline is about a month for a driveway, though sealer instructions and weather decide the right moment.
Often not exactly. Patches and new panels differ in color and texture from weathered concrete. We can discuss resurfacing or staining options if matching matters to you.
Describe the project and the surface you have now, and we will reply with what we need to know.