Garage Floor Cracked Or Uneven – How Do You Fix It?

Last Updated on July 16, 2023 By Emma W. Thomas

To fix a cracked or uneven garage floor, follow these steps. For small cracks, use a concrete patching compound, filling the gaps and smoothing the surface. For larger cracks, clean out debris, apply bonding adhesive, and fill with a concrete mix. For uneven areas, grind down high spots, fill low spots with a self-leveling compound, and smooth the surface. For severe issues, consider resurfacing the entire floor with a concrete overlay.

How To Fix A Cracked Garage Floor

Fix A Cracked Garage Floor

Before you decide to fix your cracked or uneven garage floor, you must assess what caused the crack. Some cracks can be small tinny ones less than an inch wide and very short. Others can be wide and be the full length of your garage. However, most cracks will be between the two sizes. 

For some cracks, especially the small ones, you can easily fill them, while others require more than a filling. Again the cause of a crack might be a one-time thing, like an earthquake or a foundational cause that requires more work to repair. 

Depending on the cause and your skills, you can decide whether to call a professional or do it yourself.

Here are some of the steps you can follow to fix your garage floor;

Step 1: Clean Out The Cracked Area 

First, use a metal or a normal brush to get all the debris, dirt, stones, loose pebbles, and any foreign material out of the crack. The main goal is to clean the area by removing any loose materials or stones that are cracking or crumbling.

Depending on the size and shape of your crack, you can use a crack chaser to make it straight and even. A crack chaser is a special saw blade that helps make cracks uniform. Once the crack is clean and uniform, you can now move on to the next step.

Step 2: Fill In The Crack On Your Garage Floor.

The best way to fill the crack depends on its size. For small cracks, you can use a self-mixing filler. While for large and long cracks, you will have to mix it yourself. It will take a lot of filler, and there is no self-mixing filler for large quantities. 

Buy the materials and different types of fillers you will need from your local stores and hardware. Ensure the filler is waterproof to prevent water from sipping in the ground and accumulating underneath your floor. The climatic conditions of your area also determine how waterproof your filler should be. Always consult the expert or even the supplier to get the ideal one. 

When filling, follow the product’s instructions that come with it, as each process might vary for different fillers. 

Once done, let the filler rest. It might take some time to dry up completely, but some sunlight or UV light can speed up the process.

How To Fix An Uneven Floor

All floors are not always completely flat; some might tilt slightly, causing zero negative effects. However, sometimes the uneven floor might be too much to bear as it is too slanted on one side. An imbalanced garage floor can leave a gaping hole at the foot of your garage door; this is an inconvenience as pests might get into your home through it. Below are the different ways you can use to fix the uneven garage floors: 

1. Use Of A Levelling Compound For The Small Issues

This is a common method mainly used on small regions of interior floors. You will need a leveling compound or mortar to fix minor issues and slants. If you pour it over a large area, it will crack after it dries up.

After applying the leveling compound on an uneven region, clean it thoroughly to work well.

2. Slab Jacking With Slurry

Slab jacking with slurry is expensive but is the most common method to level out large slabs of concrete. However, it is cheaper than breaking the entire concrete floor. It utilizes the existing slab and only requires minor touch-ups when the slab jacking works. DIY might be difficult; therefore, it would be best to get professional help. 

Slab jacking is done by drilling holes about three inches into the concrete floor. These holes are drilled in a sequence that will not break the slab at any point. The slurry is injected into the holes and goes under the existing concrete slab. The product comprises sand, gravel, ash, and water and can take about one day to dry up completely.

3. Slab Jacking With Polyurethane Foam

Slab jacking with polyurethane is similar to slab jacking with slurry, but it is considered a better solution. The polyurethane foam is preferred over slurry as it is easy for technicians to predict how far it will expand.

However, the technic used in incorporating the polyurethane foam is the same as the one used to inject the slurry. The only difference is that polyurethane needs larger holes to be drilled into the concrete. A calculated amount of foam is injected into the slanted concrete slab. After the foam has rested, a concrete patch is added to the drilled holes to cover them.

Polyurethane foam is lighter than the slurry mixture. This reduces the load weight on the ground under the concrete floor. Even though the foam is lighter, it does not sink when applying a heavy load on the garage floor.

List of Equipment you will need to Fix a Cracked Or Uneven Garage Floor

To fix a cracked or uneven garage floor, you will need the following equipment:

  • Safety gear: Safety goggles, dust mask, and work gloves to protect yourself during the repair process.
  • Chisel and hammer: For removing loose concrete and debris from cracks.
  • Wire brush: To clean the crack and surrounding area, ensuring good adhesion of the repair material.
  • Concrete patching compound: For filling small cracks and minor surface imperfections.
  • Bonding adhesive: To enhance the bond between the existing concrete and the repair material for larger cracks.
  • Concrete mix or self-leveling compound: Depending on the size of the crack or uneven area, choose an appropriate material for filling and leveling.
  • Trowel: For applying and smoothing the concrete mix or self-leveling compound.
  • Concrete grinder: If dealing with an uneven surface, a grinder can help grind down high spots.
  • Bucket and mixing tools: To mix the concrete or leveling compound as per the manufacturer’s instructions.
  • Broom or vacuum: For cleaning up dust and debris after the repair.

When Do You Need To Fix The Uneven Garage Floor

There are three critical scenarios where you will have to fix an uneven garage floor. These include;

1. Garage Floor Tilting Towards The House

In this scenario, the floor starts to sink and slant on the side nearest to your house. This slant can lead all the water collecting on your driveway into your home. Such an instance is critical and must be fixed as soon as possible.

2. Gaping Garage Door

The garage door may be slanted so that it does not completely close on the bottom edge. When the floor slants, you can notice it earlier if there is some light coming in from the bottom of the garage door. This is a sign that alerts you of the uneven floor.

3. When Critical Services Are Affected

If you keep your washers and dryers in the garage, they won’t function well if they are tilted and not on a flat surface. You will have to fix the uneven floor to use the equipment. 

What Causes Garage Floors To Crack?

Garage floors may crack or become uneven over time due to various reasons highlighted below: 

1. Shrinkage

Naturally, a concrete floor will shrink over time. When shrinkage happens, cracks will form on the floor as it adjusts.

2. Poor Installation

A poor floor installation will leave your floor vulnerable to cracks. You will have to install reinforcements on the floor to resist all forces that might cause damage. For instance, when a floor is lightly installed over the soil with no foundation, it will crack fast before enjoying the services.

3. Poor Drainage

Water is a very powerful agent, and it can cause damage to many different materials. When the area around your garage floor is always wet, the chances of the ground beneath letting go and sinking are very high. A good drainage system can help reduce issues caused by water.

4. Settlement

Settlement happens when the ground that your house or building is sitting on moves and shifts as time goes on. When this happens, it causes great pressure on the garage floor, which results in your house tilting to one side or the other.

As a homeowner, you should take settlement cracks very seriously as they can signify bigger risks. It can absorb water and keep it under your garage floor. Waterlogged soil on potentially unstable ground can collapse your garage and house.

When to Call a Professional to Fix a Cracked Or Uneven Garage Floor

You should consider calling a professional to fix a cracked or uneven garage floor in the following situations:

  • Extensive damage: If the cracks are large, deep, or widespread across the garage floor, a professional can assess the severity and provide appropriate solutions.
  • Structural issues: If you suspect the cracks are due to underlying structural problems, such as foundation issues, it’s best to consult a structural engineer or professional contractor.
  • Lack of experience: If you don’t have experience in concrete repair or leveling, hiring a professional ensures the job is done correctly and prevents further damage.
  • Safety concerns: If the floor is severely uneven, causing trip hazards or affecting the functionality of the garage, a professional can address the problem safely and efficiently.
  • Time and convenience: If you lack the time or resources to handle the repair yourself, hiring a professional allows you to focus on other priorities.
  • Warranty coverage: If your garage floor is still under warranty, attempting DIY repairs may void the warranty. Hiring a professional ensures compliance with warranty terms.

Final Thought

An uneven or cracked garage floor can be fixed. The solution depends on how big the issue is; you can hire a professional or fix it yourself. The bottom line is; you should not ignore cracks and uneven garage floors as they can signal an impending risk that might cause a lot of damage.