Mudjacking / slabjacking A concrete leveling method where a pressurized mixture of water, soil, sand, and cement is pumped beneath a sunken slab to raise it back to its original position.
While mudjacking can lift sunken slabs on private patios or driveways, it is rarely accepted as a permanent fix for NYC public sidewalks. The underlying cause of settling in NYC—such as leaking utility lines or poorly compacted urban soil—often causes mudjacked slabs to sink again over time. Re-pouring the sidewalk flag over a newly compacted subbase is the DOT-approved solution.
Frequently Asked Questions About Mudjacking / slabjacking
What is mudjacking?
A concrete leveling method that pumps a pressurized slurry beneath a sunken slab to lift it back toward its original position.
Is mudjacking accepted for NYC sidewalk violations?
Generally not as a permanent fix. DOT expects the flag to be replaced over a properly compacted subbase.
Why do lifted slabs sink again?
Because the cause, such as a leaking utility line or poorly compacted fill, is still present after the lift.
Where does mudjacking work well?
On private patios, walkways and driveways where the settlement cause has been addressed and code compliance is not at issue.