Ideally, your cars should move, but your garage should not.
 

In construction, every detail matters, especially when it comes to backfill for a foundation. Our team took on the challenge of addressing structural concerns in a residential garage located in Montgomery, a suburb of Cincinnati. Situated on a slope, the property posed a significant issue with a large portion of the rear foundation exposed. The backfill that was used in the construction of this garage had settled, causing problems with the foundation walls.

 
A foundation is typically engineered to endure soil pressure exerted from the exterior, with walls, footers, and framing collectively providing lateral resistance.
However, in a case like this, the reversed arrangement meant that the strength of the two walls and their anchorage to the home and slab were the sole defenses against this internal pressure. Additionally, the weight of vehicles, the concrete slab, and the garage structure all compounded the force pressing down and out on that wall. Mishandling the construction of such a building could easily lead to wall failure.

 
At this home, vertical and diagonal cracks, leaning walls, and a visible gap between the slab and foundation all hinted at underlying stress and movement.
 

    Corner vertical crack in the back of a garage

To address the issue, the homeowner enlisted the expertise of Cole Engineering. Cole determined that soil pressure beneath the garage slab was exerting excessive force on the foundation walls from within.

To prevent movement of a garage like this the right backfill is necessary.
 

Whenever you add fill to establish a foundation for a structure on a hill, you must take care to mitigate future settlement issues. This includes proper anchorage as well as the right fill.

The engineer designed an anchorage system for a new garage slab and provided guidance for backfilling the area to prevent settling. In this case, they called for a granular, gravel-based fill which is not compactable and allows any moisture to drain away.

To reinforce the structure further, we used epoxy injections to seal and strengthen the existing cracks.  Effectively halting further deterioration and preventing water intrusion. Additionally, new drainage systems installed alongside the garage will further mitigate hydrostatic pressure on that wall.

   

These homeowners are very happy to know that their garage is not going anywhere, thanks to Cole Engineering and Hughes Construction.

Are you experiencing similar signs and symptoms of movement at your home, garage, or business? Contact us for guidance or visit our preferred engineers page to connect with a licensed structural engineer.

 

  • Backfilled garage showing cracks and gaps
  • Backfilled garage wall showing cracks
  • Overhanging brick in backfilled garage
  • Exposed backfill in garage
  • exposed wall in backfilled garage