How often do you think about your garage flooring? Unless you’re building, repairing or remodeling, you likely don’t give it much thought. Nevertheless, it’s there in the background doing its job – supporting the weight of your vehicles, shrinking and expanding with the temperature, and dealing with the odd paint or oil spill. Over time, however, all these activities can cause cracks and crumbling in your concrete flooring. Although you might be tempted to repair these cracks with commercial DIY products such as epoxy, they tend to recur. Here’s why:

  • Concrete cannot stretch or bend without breaking because it is not a ductile material.
  • It can shrink and expand during temperature fluctuations, but this is still likely to cause cracking.
  • As the soil under your garage settles and shifts, it can cause cracks that are beyond your control

Most often, when contractors are pouring your concrete slab, they create deep grooves or saw – cut joints to discourage cracking. These are called contraction joints and their purpose is to encourage any cracks to follow the groove instead of wandering across your garage floor surface. Contraction joints can prolong the life of your garage flooring by minimizing cracks. However, you’re still at the mercy of the soil underneath the floor which can undermine your best efforts.

Reasons Why Your Garage Slab is Sinking

Unlike a few cracks in your concrete, a sunken slab is no quick fix. And sometimes, depending on the cause, it’s better to address any underlying soil compaction issue and start fresh with a new slab altogether.

Garage slab replacement

Garage Floor Slab Replacement

If you’ve noticed your concrete slab sinking, here are some reasons why that might be occurring:

  • Water Damage: Inadequate floor drainage and moisture from cracks in your slab foundation.
  • Temperature Extremes: The freeze-thaw cycle can impact your garage flooring drastically, especially if there is zero or minimal heat source within your garage. Your climate can play a big role in this and Northern communities, like ours in Calgary, are most at risk for this type of damage.
  • Soil displacement: The type of soil and how well it was compacted before your concrete floor was poured can make a big impact on the life and quality of your concrete slab.
  • Low-Quality Concrete Mix: Unfortunately, not all aggregates are up for the job. Low quality aggregates such as iron pyrite can lead to crumbling and corrosion over time.
  • Pitting and Settling: In Northern climates, salt can cause pitting in your garage foundation, more often than in the South. Additionally, shifting soil over time can cause cracks or sinking to occur.

Large cracks in your slab and soil displacement issues can cause your floor to sink in sections. Keep an eye out for water pooling in one corner or even visible uneven flooring sections. These signs may indicate that the garage floor is sinking.This can be a big problem for attached garages, which can cause water to seep into your home. One way to combat this is to ensure that the outside soil level, surrounding your garage is at least six inches below the level of your garage floor.

Stained Floor Project in Calgary Before and After

Garage Floor with Cracks Repaired & Stained Finish

Concrete Repair Cost vs Concrete Slab Cost

When considering the cost of concrete slab replacement or repair, it’s good to follow this rule of thumb: If the repair will require more than two inches of material, replacement is probably the best option. When there is less than two inches to replace, there are a good number of market products that can restore your slab’s structural integrity and aesthetic appeal. If you’re considering replacement, here are a few things to consider:

  • Consider the age of your concrete slab in addition to the extent of the damage before making a decision.
  • Overhead clearance can be an issue if the repair involves pouring a layer of cement over an existing concrete slab.
  • The time-frame of your project can be a determining factor. How long are you able to have your structure out of commission?
  • In addition to functionality, consider aesthetic appeal when contemplating the cost of concrete repair vs. replacement.

Do you have questions or concerns about your garage flooring or concrete slab? Elite Concrete can provide expert advice on how to handle cracks in your concrete, a sinking slab, and how to prolong the life of your garage floor. If you’re unsure whether it’s time to repair or replace your garage flooring, contact us to assess your site. Act now before your small cracks turn into a bigger problem.