DIY: Lifting & Levelling a Sidewalk

Mark two drill holes with chalk on the sidewalk where the slab is sinking. Both holes must be 1 foot in from the sides and spaced 3 to 8 feet apart to cover the length of the sunken area.

Use a masonry drill with a 2-inch bit to drill through the slab where you marked the holes.

Feed a hose with a 2-inch nozzle through the lowest hole until you hit the ground below. Don’t try to push the hose any further into the ground or loose dirt could clog the nozzle.

Fix the other end of the hose to the slabjacking pump, and tighten a clamp over the connection to prevent the hose from getting loose or popping off.

Scoop cementious grout sold specifically for slabjacking into the pump with a shovel.

Turn on the pump and fill the void between the slab and foundation. Move the hose to the next hole and pump until the void is filled.

Insert the hose back in the first hole and turn the pump back on. Since the void beneath is filled, the pump can now hydraulically lift the slab by pressurizing the grout. Watch the slab and move the hose to the second hole once it rises 1 inch.

Continue to pump grout into each hole, lifting the sidewalk 1 inch at a time until it is near its original height.

Place a bubble level on the sunken surface between the two holes. Pump grout until the bubble rests at the center of the level.

Remove the hose and wipe off any remaining grout from the two drill holes with a cloth. Use a putty knife to fill the holes with stiff mortar. Add it in small amounts at a time, tamp it with a putty knife and add more until the holes are overfilled. Cut off the top so the patches are level with the rest of the sidewalk.