Do It Yourself: Concrete Sidewalks

Concrete Form

• 1

  Break 12-inch hardboard in two to obtain a 6-inch width and stake it down with temporary stakes in the shape you want for the sidewalk. This hardboard represents the shape but will be used for only one side at this point.

• 2

  Spray along the hardboard with spray paint to create an outline of the sidewalk where you will begin digging. To do the opposite side, use a spacer block to create uniformity and spray along the entire length of the sidewalk to have the complete outline.

• 3

  Slice the sod out of the outlined area using a sod cutter. Use a shovel to dig 6 inches deep within the outline as well as 3 inches outside the outline on each side for the forms. Save the topsoil to pack in against the forms later.

• 4

  Position hardboard siding to use for the forms so the form is 1 inch above the surrounding grass along the edges of the sidewalk. Bend the hardboard for smooth curves in the sidewalk.

• 5

  Place stakes in the ground beginning 1 foot from the end of the form and continuing every 3 feet for the length of the form and screw the hardboard forms using two 1 1/4-inch drywall screws to the inside of each stake.

• 6

  Screw 18-inch form material against the inside of the form using the drywall screws along the length of the form.

• 7

  Repeat to create forms on the opposite side of the sidewalk, using a piece of 1-by-4-inch board, or homemade gauge board, that is slightly wider than the sidewalk. Place a level on top of the gauge board to ensure both sides are the same height.

Preparation

• 8

  Pack the entire base of the soil with a plate compactor and spread gravel between the forms to a height of 4 inches. Compacting the gravel is not necessary.

• 9

  Cut off the top of the stakes to match with the height of the forms.

• 10

  Place reinforcing mesh at the end of the sidewalk form and create a ballast at the end. A ballast is an object that is used to stabilize the mesh while you unroll it. This can be a stake that is placed through one end of the mesh and hammered into the ground on each side.

• 11

  Unroll the mesh along the entire length of the sidewalk, cutting it with bolt cutters so the edges are 3 inches inside the forms. When unrolling the mesh, hold it down with your feet as you move along the length. To help eliminate the curl in the mesh from being rolled, slightly bend the mesh back in the opposite direction.

• 12

  Overlap each end of the mesh by 6 inches and wrap the ends back onto the sheet with the bolt cutters to secure the position.

• 13

  Place small pieces of concrete under the mesh so that the mesh is 2 inches above the gravel.

Pouring Concrete

• 14

  Pour the concrete a few feet at a time so that it is slightly above the height of the forms. Use a steel rake to push or pull the concrete and flatten the concrete with a screed board. A screed board is a piece of 2-by-4 that extends beyond the sidewalk's width by 1 foot. When flattening the concrete, use a back-and-forth sawing motion until you reach the end of the concrete. Pour and repeat this application, flattening until the entire sidewalk has been poured.

• 15

  Flatten the concrete surface with a bull float immediately after using the screed board. When working with the bull float, slightly lift the front edge of the float when pushing away from you and lift the back edge of the float when pulling it toward you.

• 16

  Allow any water that has bled to the surface to disappear and smooth out the surface using a magnesium float. When using the float, always lift with the leading edge as you smooth the surface in a back-and-forth motion and begin at the start of the pour, moving down toward the end.

• 17

  Round the edges of the form using an edging tool and working in a 1-to-2-foot area at a time. When working with the edging tool, move it in a back-and-forth motion and work your way down the length of the sidewalk.

• 18

  Cut control joints into the sidewalk using a groover every 5 to 6 feet; all segments should be the same length.

Finishing

• 19

  Rest a concrete broom on the opposite side of the form and pull it slowly and directly toward you. Continue to "broom" the concrete throughout the length of the sidewalk, ensuring each stroke overlaps the previous stroke by 6 inches. If you feel the concrete clumping or is too wet to efficiently broom over it, smooth it out with the magnesium float and attempt again in 15 minutes.

• 20

  Cover the concrete with 4-mil plastic once you can no longer leave an impression with your fingertip, anchoring the edges with brick so it does not fly away. Leave it on for one day. Remove the plastic after a day and slow the curing process over the next three or four days by sprinkling the sidewalk with water occasionally.

• 21

  Remove the forms from the sidewalk no sooner than one day after you pour the concrete. The concrete takes one month to reach its full strength but can be walked on the day after you finish.