What is Slabjacking?
If you’ve noticed your driveway, sidewalk, or concrete foundation sinking into the ground, you might wonder what options are available to fix it. Slabjacking is a proven solution to lift and level sunken concrete surfaces quickly and effectively.
This method not only saves you time and money but also restores the safety and appearance of your property without needing a full replacement. In this guide, we’ll explain how slabjacking works, the equipment and materials used, and when it’s the best choice for your concrete repair needs.
How Does Slabjacking Work?
Slabjacking involves drilling small holes into the concrete slab and injecting a grout mixture or polyurethane foam beneath it. This material fills the gaps and voids in the soil, raising the slab back to its original level. The process is quick and efficient and usually takes just a few hours, depending on the size of the area.
Equipment and Materials Used in Slabjacking
Slabjacking requires specific equipment and materials to ensure a successful repair. Here are the main tools and materials used:
Rock Drills
Rock drills create small holes in the concrete slab, allowing the grout or foam to be injected underneath. These drills are powerful and must be maintained regularly to ensure they operate efficiently. Regular maintenance includes checking for wear on drill bits and ensuring proper lubrication.
Grout Mixers
Grout mixers blend the grout materials to the right consistency. Proper maintenance is crucial to prevent clogging and ensure smooth operation. Regular cleaning and inspection of the mixing paddles and internal components help extend their lifespan.
Types of Grout
The grout used in slabjacking can vary depending on the job. Common types include sand-based grout and mixtures of cement, water, and additives. Each type has unique properties that determine how well it fills voids and stabilizes the slab.
Polyurethane Foam
Polyurethane foam is another material used in slabjacking, offering many advantages over traditional grout. This lightweight foam expands rapidly after injection, filling voids and lifting the concrete slab quickly.
Polyurethane foam sets in just minutes, providing a strong, durable solution that resists moisture, erosion, and soil shifts. The injection process is also cleaner and less invasive, requiring fewer holes and causing minimal disruption to the surrounding area.
Why Polyurethane Foam is Superior to Grout Injection
When it comes to slabjacking, both polyurethane foam and traditional grout injection can lift and level concrete slabs. However, polyurethane foam offers several key advantages that make it a superior choice for most concrete repair projects.
1. Faster Results
Polyurethane foam sets much faster than traditional grout. While grout may take several hours or even days to fully cure, polyurethane foam typically hardens and reaches its maximum strength within 15 minutes. This rapid setting time means you can use the repaired area almost immediately, reducing downtime and inconvenience for homeowners and businesses.
2. Greater Durability
Polyurethane foam is highly durable and resistant to factors that often compromise grout over time, such as moisture and erosion. Unlike grout, which can crack or degrade due to water infiltration or shifting soils, polyurethane foam maintains its form and integrity for many years. This durability results in a longer-lasting solution that reduces the need for future repairs.
3. Lightweight and Sturdy
Polyurethane foam is much lighter yet stronger than traditional grout mixtures. This lighter weight puts less pressure on the underlying soil, minimizing the risk of further sinking or settlement. Grout, on the other hand, is heavy and can add significant weight to an already unstable foundation, potentially causing more problems over time.
4. Minimal Disruption
The polyurethane foam injection process is cleaner and less invasive than grout injection. The foam expands to fill voids and gaps with minimal drilling and no need for large holes or extensive excavation. This process results in less mess and disruption to your property, making it an ideal choice for residential and commercial settings alike.
5. Waterproof Material
Polyurethane foam also offers better insulation and waterproofing properties than traditional grout. Its closed-cell structure helps block moisture and air from seeping through, providing additional protection against water damage and reducing energy costs. Grout, in contrast, is porous and can absorb moisture, leading to potential issues like mold growth or erosion.
When to Use Slabjacking
Slabjacking is a great choice in many common situations:
- Sunken or Uneven Concrete Slabs: Use slabjacking to lift and level cracking or uneven concrete surfaces like driveways, sidewalks, and patios.
- Minor to Moderate Concrete Damage: Choose slabjacking when dealing with minor to moderate cracks or surface damage, as it stabilizes the slab and fills gaps to prevent further damage.
- Areas with Good Soil Conditions: Opt for slabjacking in areas with stable soil that is not overly moist or filled with organic material. The grout or foam bonds better in these conditions.
- Cost-Effective Repair: If you’re looking for an affordable and quick way to restore concrete surfaces, slabjacking offers a cost-effective alternative to complete slab replacement.
When Not to Use Slabjacking
There are situations where slabjacking may not be the best solution:
- Severely Damaged Concrete: When concrete slabs have severe cracks, are crumbling, or have broken into chunks, slabjacking may not provide a strong enough repair. Replacing the slab is often a better choice.
- Poor Soil Conditions: Slabjacking may not be effective in areas with poor soil conditions, like loose soil, soil with a lot of organic material, or soil that is saturated with water.
- Frequent Foundation Problems: If your home or structure has recurring foundation issues, such as frequent settling or shifting, slabjacking may only provide a temporary fix. You may need a stronger solution, like foundation piers.
- Extensive Tree Root Damage: If tree roots have caused the slab to lift or break, handle the root problem before any concrete repair. In these cases, slabjacking alone may not be effective.
Choose the Right Solution With Groundworks
Knowing when to use slabjacking and when to consider other options is key to a successful concrete repair. At Groundworks, we have industry-leading concrete and foundation solutions.
Our experts assess the condition of your concrete and soil and provide you with the best fix to meet your needs. Contact us to schedule a free inspection, and let us restore your concrete to its best condition!
Slabjacking FAQs
Common problem signs indicating that your concrete may need to be lifted and repaired include cracks, heaving or sinking areas, or visible gaps between slabs. Unevenness can cause safety concerns, such as tripping hazards, and can also negatively impact the aesthetics of your property.
The costs of concrete lifting vary based on project-specific details like the size of the concrete area and the severity of the damage. PolyRenewal™ injections are cost-effective compared to complete slab replacement or DIY installations. Contact a local professional for a free concrete inspection and estimate.
Concrete lifting works for a wide range of concrete structures, from small residential projects to large commercial or industrial applications. However, if the concrete is severely damaged, it may need to be replaced entirely.
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