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What You Need To Know About Garage Foundation Repair

Table of Contents

1. Signs There Might Be A Problem With Your Garage’s Foundation
2. Repair Options For A Settled Garage Foundation
3. But, The Problem Might Be With The Garage Slab Only
4. Repair Options For A Sinking Garage Slab
5. How To Prevent Problems With A Garage’s Foundation

Searching for information about garage foundation repair? If so, you’ve landed on the right page because that’s what we’re going to review in this article. We will discuss the signs there might be a problem with your garage’s foundation, repair options for a garage foundation, and more.

Signs There Might Be A Problem With Your Garage’s Foundation

Like houses, garages have foundations that can settle into the ground unevenly (i.e., differential settlement). Here are some signs that may indicate your garage’s foundation is suffering from differential settlement:

  • Floor or wall cracks – Cracks in a garage’s walls, floor, or ceiling could be a sign of foundation damage. Wall cracks might be horizontal, diagonal, or a series of vertical cracks next to each other. Watch out for cracks that go across a ceiling and down a wall.
  • Uneven garage floor – A sloping or uneven garage floor is another indication there might be a foundation problem. This could cause water to pool in certain areas leading to further damage and potential safety hazards.
  • Sticking doors and windows – If your garage door or windows are sticking or difficult to open and close, it could be due to a foundation issue. The windows and doors become misaligned due to the foundation shifting and settling.
  • Gaps between the wall and the ceiling – If you notice any gaps between the walls and ceiling of your garage, it could be due to foundation trouble.
  • Stair step cracks in brick or masonry – This is a sure sign the garage’s foundation has moved.

If you notice any of the above – or anything else that strikes you as suspicious – consult a professional foundation repair contractor to assess your garage’s foundation and make any necessary repairs. It’s better to address the problem sooner rather than later to prevent further damage and ensure the safety of your garage.

Repair Options For A Settled Garage Foundation

The most common repair solution for differential settlement is underpinning. Underpinning involves using piers to extend the foundation down to soil that can support it. The piers are driven (or turned) into the ground until they reach a stable, load-bearing stratum, such as bedrock or dense soil. Once the piers are in place, a synchronized hydraulic lifting system raises the foundation to maximum practical level, which means the foundation is raised as much as possible without causing damage.

Underpinning is a minimally-invasive repair solution that shouldn’t take more than a few days to complete. Once the piers are installed, they provide a permanent solution that can last for the lifetime of the structure without needing any maintenance.

But, The Problem Might Be With The Garage Slab Only

It’s possible the problem is with the garage slab only. This can happen when the building’s design didn’t call for the garage slab to be connected to the foundation perimeter. If so, it will require a different repair solution, usually polyurethane foam injection.

Repair Options For A Sinking Garage Slab

If the garage slab is not connected to the perimeter foundation, a common repair solution is polyurethane foam injection. This will lift and level the sunken garage slab.

Raising a sunken garage slab using polyurethane foam injection usually only takes a few hours, allowing homeowners to quickly return to using their garage. The general process is as follows:

  • Small, dime-sized holes are drilled into the slab.
  • The polyurethane foam is injected under the sunken slab via the holes.
  • The foam immediately begins to expand, filling voids and raising the slab.
  • Finally, the holes are patched with a compound that closely matches the color of the slab.
  • Fifteen minutes after the repair, the slab is ready for use again.

The foam material used in this type of repair is water-resistant, making it a durable and long-lasting solution for a sinking garage slab. Polyurethane foam injection costs less than replacing the slab, making it an attractive option for homeowners looking for an affordable solution.

Note: In some cases, a garage slab might be so severely damaged that it will need to be replaced. However, in most cases, a sunken garage slab that isn’t connected to the perimeter foundation can be repaired using polyurethane foam injection.

How To Prevent Problems With A Garage’s Foundation

The good news is there are some things you can do that will help prevent problems with your garage’s foundation. These include the following:

  • Regrade the yard around the foundation – The ground around the garage should slope away from the garage to prevent groundwater from draining toward the garage’s foundation.
  • Install downspout extensions – Downspouts direct rainwater away from the foundation. When the downspouts are too short, water can pool around the foundation, causing damage over time. Extensions are inexpensive, easy to install, and channel water away from the foundation before release.
  • Clean gutters regularly – Gutters can become clogged with leaves and other debris, preventing water from draining correctly and causing water buildup around the foundation.
  • Install a drain tile system – A drain tile system prevents excess moisture from building up in the ground around the foundation. The system can be installed around the outside perimeter of the garage’s foundation at the footing level. Excess moisture flows into the perforated drainage pipe and toward a sump pit. Once the pit is full of water, a sump pump turns on and ejects the water away from the garage’s foundation.
  • Keep trees away from the garage – The roots of large trees can invade the ground under the foundation and cause a lot of trouble.

If you think your home’s garage might need foundation repair, contact us today to schedule an evaluation. We serve all of Northern California.

Steve Egloff

Steve Egloff

Founder of Bay Area Underpinning

Steve is the Founder of Bay Area Underpinning, a foundation repair company serving the San Fransisco Bay Area, California. Bay Area Underpinning was founded in 2005 with the goal of providing a cost-effective, engineered solution to foundation settlement problems with an emphasis on educating customers to make them feel comfortable with the various methods of foundation repair.

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