Garage Apron Leveling & Repair
Sunken Garage Apron? It Can Usually Be Lifted, Not Replaced.
Your garage apron is the concrete slab that sits between your garage floor and your driveway. When it settles, Benchmark Concrete Raising lifts it back to grade by injecting high-density polyurethane foam into the voids underneath. Most aprons are done in about two hours, with no demolition and no new pour, and the slab is driveable before the crew leaves the property.
- A garage apron sinks before the rest of the driveway because it sits on backfill soil, not on undisturbed ground.
- Lifting a garage apron typically costs 50 to 70 percent less than tearing it out and pouring a new one.
- The foam cures in about 15 minutes, so you can park on the apron the same day.
Why the Apron Goes First
Why Does the Apron Sink When the Rest of the Driveway Is Fine?
Because the apron sits on backfill soil from the original foundation excavation, and the rest of your driveway sits on ground that was never disturbed.
When your house was built, the excavation for the foundation was dug wider than the walls themselves. That trench was backfilled with loose soil once the foundation was in. Backfill never returns to the density of the ground it replaced, no matter how well it is tamped, and it keeps consolidating for decades. Your garage apron is poured directly over it.
Twin Cities soil makes it worse. The metro sits on clay-heavy glacial deposits that swell when wet and shrink when dry, and Minnesota's freeze-thaw cycle drives that movement hard every winter. Add roof runoff and driveway drainage that both concentrate at the same transition point, washing fine material out of the backfill, and a void opens under the slab. The concrete then settles into it.
The apron also carries more traffic than any other slab on the property. Every vehicle you own crosses it every time it leaves the garage.
What Settlement Actually Costs You
What Does a Settled Garage Apron Actually Do?
It reverses the drainage at your garage door. A settled apron tips back toward the house and sends rain and snowmelt under the door instead of out to the driveway.
The lip at the threshold is the part people notice. The water is the part that costs money.
- Water runs into the garage. An apron pitched back toward the building sends rain and snowmelt under the door and across the floor instead of carrying it out to the driveway.
- The door seal stops working. A garage door's bottom seal is designed to compress against a level slab. Once the apron drops away from it, the gap stays open to water, blowing snow, cold air, and rodents.
- Meltwater pools against the foundation. Water that collects at the transition point freezes, expands, and accelerates the same settlement that caused the problem.
- The lip catches equipment. A raised edge at the door is what shovel blades and snowblower housings hit first, and it is a real trip hazard for anyone carrying something out to the car.
- Salt gets tracked and held. Road salt in standing meltwater sits on the slab and on the edge of your garage floor rather than draining off.
Lifting the apron corrects the pitch at the same time it closes the gap. That is the part homeowners tend not to expect: the drainage fix and the cosmetic fix are the same job.
Lift or Replace
Should You Lift the Apron or Replace It?
Lift it, in most cases. Lifting costs 50 to 70 percent less, takes about two hours instead of several days, and fills the void that caused the settlement in the first place.
| Polyurethane Foam Lifting | Tear Out and Replace | |
|---|---|---|
| Cost | 50 to 70 percent less than replacement | Full price of demolition, disposal, and a new pour |
| Time on site | About two hours, start to cleanup | Multiple days, often multiple crews |
| When you can park on it | Same day. Foam cures in about 15 minutes | Roughly a week before vehicle traffic |
| Garage access during work | Blocked for the length of the visit only | Blocked until the new slab cures |
| The void underneath | Filled and stabilized as part of the lift | Must be recompacted separately or the new slab settles too |
| Site impact | Dime-sized holes, patched before we leave | Heavy equipment, debris haul-off, disturbed landscaping |
The last row is the one worth reading twice. Replacing a slab without addressing what is underneath it puts new concrete on the same unstable backfill that sank the original.
Straight Answers
When Is an Apron Too Far Gone to Lift?
When the slab is cracked through in several places, spalling badly, or broken into pieces that will not move as a unit. Foam will raise the fragments without restoring a sound surface, so we tell you to replace it instead.
Roughly 70 percent of the sunken slabs we evaluate are good candidates. The concrete is intact and the problem is underneath it. You can find out which category you are in before anyone comes out: send us a photo of the apron and the door threshold, and we will give you an honest read.
Aprons rarely settle alone. If your driveway, sidewalks, or front steps have dropped as well, they can usually be lifted in the same visit. More on the method itself is on our polyurethane concrete raising page.
Common Questions
Garage Apron Leveling: FAQ
What is a garage apron?
A garage apron is the section of concrete between your garage floor and the start of your driveway. It is usually four to ten feet deep and the full width of the garage opening. It carries every vehicle that enters or leaves the garage, and it controls whether water drains away from the building or back into it.
Can a sunken garage apron be lifted instead of replaced?
In most cases, yes. If the slab is structurally intact, polyurethane foam lifting raises it back to grade in about two hours at 50 to 70 percent less than replacement cost. We evaluate the apron before committing, and if lifting is not the right call we will tell you before you schedule anything.
Why did my garage apron sink when the rest of my driveway is fine?
Because the apron sits on backfill soil from the original foundation excavation, and the rest of your driveway sits on undisturbed ground. Backfill keeps consolidating for decades, and clay-heavy Twin Cities soil combined with Minnesota's freeze-thaw cycle opens voids under that slab first.
Water runs into my garage when it rains. Will lifting the apron fix it?
Usually, yes. When water enters at the garage door, the cause is almost always an apron that has settled and now pitches back toward the building. Raising the slab to correct grade restores drainage away from the foundation and closes the gap under the door seal at the same time.
Will the apron sink again after it has been lifted?
Rarely, when the void is fully filled and the slab is brought back to correct grade. High-density polyurethane foam does not absorb water, compress under load, or wash away, so the freeze-thaw forces that moved the original soil do not affect the repair material. Ask about the specific warranty terms when you schedule your estimate.
How long does the repair take and when can I park on it?
About two hours from arrival to cleanup, and you can park on it the same day. The polyurethane foam cures in roughly 15 minutes, so the apron is driveable before the crew leaves. There is no cure time to plan around and no need to park on the street for a week.
The Bottom Line
Do Not Replace an Apron You Can Lift
Benchmark Concrete Raising lifts and levels sunken garage aprons in Edina, Bloomington, Minnetonka, Eden Prairie, Plymouth, Maple Grove, St. Louis Park, Woodbury, Minneapolis, St. Paul, and communities throughout the Twin Cities metro. Estimates are free.
Send us a photo of your apron and the door threshold, and we will give you an honest read before anyone shows up.
