Stabilizing a Sinking Fire Station in Franklin, Ohio

Challenge

Back in 2023, we were called to this fire station to stabilize the foundation beneath the living quarters and the rest of the station - excluding the garage. The slab foundation under the living quarters was sinking into unstable soil, which caused the finished flooring to crack and break. For the firefighters, this was more than just a nuisance; it disrupted their living space. They wanted the sinking to stop so they could redo the floors without worrying about further damage.

Firefighters know a thing or two about structures, so they recognized the issue early and were very interested in how we could solve it. To stabilize the slabs, we used our PolyLevel foam injection system. The process is straightforward: we drill small, pea-sized holes into the sinking concrete and inject expanding foam beneath the slab. The foam fills voids and stabilizes the soil, lifting and supporting the concrete so it won’t shift again. With this solution, the firefighters could confidently move forward with their flooring project.

Fast forward to today - the station called us back with a new concern. This time, the garage was separating from the rest of the building, creating cracks in the slab floor. For firefighters, that’s a serious issue; the garage is where they need to move quickly when duty calls, and further cracking could have made the situation much worse.

Unlike the living quarters, the garage was built with an exceptionally thick concrete slab - about a foot thick - designed to handle the weight of firetrucks and heavy equipment. The surface was also coated with epoxy for slip resistance and chemical protection. Because of the slab’s thickness and the tremendous weight it supports, our PolyLevel system wasn’t the right fit this time. Instead, we had to choose a different repair method to properly stabilize the garage floor.

Solution

This time, our Inspector designed a plan using our steel pier underpinning system. Much like our PolyLevel process, underpinning addresses the true problem - the unstable soil beneath the foundation. In this case, we installed 11 steel piers in the affected section of the garage, right where it connects to the living quarters. Since this garage slab was built separately from the living quarters, the cracking appeared along that transition point.

Normally, piers can be installed from outside the structure by digging down to the foundation. However, because this problem area was located where two different foundations meet, we couldn’t reach it from the outside. Instead, we needed to cut into the garage floor and dig down to expose the footing.

The footing is the lowest part of a foundation, designed to spread the weight of the building into the soil. Our pier underpinning system reinforces the footing by transferring that weight into deep, load-bearing soil - the dense, stable soil layers far below the surface that don’t shift over time.

Once the footing was exposed, we drove the steel piers into the ground using a handheld hydraulic tool. The piers have a screw-like design that allows them to be twisted deep into stable soil. After reaching the proper depth, we attached the tops of the piers to the footing with heavy-duty steel brackets. These brackets lock securely underneath the concrete footing, providing a permanent connection.

In some cases, after brackets are installed, we can use hydraulics to lift the foundation back into place. Fortunately, because the firefighters caught the issue early, no lifting was needed - stabilization alone was enough. Once all piers were installed, we backfilled the trenches and poured fresh concrete to restore the garage floor.

With their foundation stabilized, the firefighters can now move forward confidently. After the new concrete cures, all that’s left is for them to reapply their epoxy coating if they choose. Best of all, they no longer have to worry about their station sinking.