How to Break Up Concrete

Thinking of removing an old concrete slab or patio? If the concrete is covered in deep cracks, shows signs of settling or is flaking away in large pieces, it’s probably time to get rid of it. Demolishing concrete may seem like a daunting, expensive task but depending on the size and thickness of your slab, you might be able to tackle the project on your own.

The cost to have a professional remove a concrete slab varies based on the size and materials it contains.  If not reinforced, expect to pay between $300 and $500. If it is reinforced, expect to pay between $500 and $799, of a 12-by-14 foot concrete slab that is approximately 4 inches thick.

Concrete Breaking Tools and Materials

In addition to gathering up tools, ask a few friends for help. While you could complete this project alone, an extra set of hands will speed up the heavy lifting.

  • Shovel
  • 12 to 20-pound sledgehammer
  • Pry bar
  • Bolt cutters
  • Mattock
  • Wheelbarrow or hand truck
  • Plastic sheeting or a dropcloth
  • Safety glasses
  • Gloves
  • Steel-toed boots
  • Hearing protection
  • Dust mask

Steps for Removing a Concrete Slab

This concrete demolition method is best if your slab is relatively small and less than 4 inches thick. If you’re attempting a larger project, like removing a concrete driveway, you will want to consider a different method, such as a jackhammer.

Step 1: Create a Void Under the Concrete

The best way to speed up concrete removal is to create a void underneath the section of slab you’re working on. If you don’t do this, the dirt or sand under the slab will absorb the blows from the sledgehammer, making it harder to break up the concrete. You can create a void by digging under the slab. Once you’ve started some cracks, you can use the pry bar to lift smaller sections of the slab and create a void. To get started, use the shovel to dig 4 to 6 inches back from the edge of the slab and about 2 inches deep. As you create cracks in the slab, you can use the pry bar to partially lift pieces instead of digging under them.

Step 2: It’s Hammer Time

Once you’ve created a void under the edges, you are ready to break up the concrete slab. Before you begin: Lay the plastic sheeting over the slab to prevent concrete from flying around. If you are close to a structure, consider covering any windows with plastic sheeting as well. Put on gloves, safety glasses, steel-toed boots and hearing protection. When you’re ready, aim your first hammer blows within 6 inches of an edge. If the slab doesn’t immediately crack, don’t hit the same spot a second time. Move a few inches in any direction and hit again.

Lay the plastic sheeting over the slab to prevent concrete from flying around. If you are close to a structure, consider covering any windows with plastic sheeting as well. Put on gloves, safety glasses, steel-toed boots and hearing protection. When you’re ready, aim your first hammer blows within 6 inches of an edge. If the slab doesn’t immediately crack, don’t hit the same spot a second time. Move a few inches in any direction and hit again.

Step 3: Pull Apart and Remove the Broken Concrete

After hammering a section, use the mattock to separate the concrete into pieces and get it out of the way.

Step 4: Repeat Steps Until Concrete Is Demolished

As you get to the middle of the concrete block, continue to dig under the edges or use the pry bar to create a void and break apart the concrete using the sledgehammer. Repeat these steps until all the concrete is loose and movable. If you are planning to lay new concrete in this spot, make sure the area is level when you’re finished. Then, you’re done. Take some time to relax and give those concrete-moving muscles a break