Denver's alley garages sit on some of the oldest slabs in the metro
Drive an alley in Berkeley or Wash Park and you'll pass rows of detached garages that predate your grandparents' mortgage, some still on their original floors. Those slabs were poured thin, on unprepared ground, in an era when a garage held a Model A and a push mower. Now they hold trucks, freezers, and home gyms, and the claystone underneath has spent a century shrinking, swelling, and settling out from under them.
Attached garages on Denver's postwar ranches tell a different story with the same ending. Builders backfilled the foundation, then poured the garage floor over that loose fill. Fill consolidates under its own weight for decades, so the slab cracks down the middle and one side drops. Newer infill homes rerun the script on a faster clock, since fresh backfill settles hardest in its first years.
Alley access, by the way, is an advantage for us. The truck pulls up behind the garage, the portable pump sits right at the slab, and the front yard never knows we were there. Detached garages that would be a nightmare to repour are often our easiest lifts of the week.
Water reaches a garage slab from three directions here
Soil failure under a Denver garage floor almost always traces to moisture, and this city supplies it in bursts.
- Spring melt: the heavy wet snows of March and April pile against the garage, then melt through the apron joint and wash fines out from under the slab edge.
- Hail-season downpours: summer storms from June through August drop water faster than clay absorbs it, so runoff streams down the driveway and under the door.
- Dry-year shrink: the opposite problem. Drought summers pull moisture out of the claystone and the soil sinks away from the slab bottom without a drop of water moving.
The result is the same tilted, cracked floor, but the cause changes the advice. Settled fill stays fixed once we lift it. An active water path will re-dig the void, so if we spot one, you'll hear about the drainage fix that makes our repair permanent.
A lift measured in eighths of an inch
The case for mudjacking a garage is everything that doesn't happen. No jackhammer inside the structure, no dumpster at the curb, no week of cure time with the cars exiled to the street. We drill 1-1/2" holes through the low sections, pump slurry until the slab planes out, and patch flush. We check the surface the whole way up, aiming for a floor flat enough for the epoxy coating plenty of garage customers are already planning. Coat after the lift, not before, and the finished floor reads as one plane.
Depth rarely stops us; we've raised slabs up to 12 inches. Past that, the slab-to-wall connection becomes the real question and we'll recommend replacement instead of selling you a lift that shouldn't happen.
One thing we need from you: a clear slab, or at least half of one. Shift everything to one side and we'll lift in two passes, which is how most packed Denver garages get done without a POD in the driveway.
Cost against the alternative
Garage floor lifts are priced by slab area and how far the floor has to rise, quoted free and in person. A single low corner near the apron is the small end of the job. A full two-car floor that's down three inches is the big end. Replacement means breaking out concrete inside a standing structure and hauling it through your driveway, which is why it costs double or triple what a lift does and why we're usually the first call worth making.
What happens when you call
Trevor shows up in person, taps the slab with a steel rod to map the voids, measures the drop against a level, and hands you a written number. If the smarter fix is replacement or a drainage repair first, that's what you'll hear instead. Trevor will tell you at the estimate when the crew can come and how long to keep the car out afterward. Call (303) 526-2222 or tell us what the floor's doing, and see lifts from around the city on our work page.