How to Make Sidewalk Molds
- 1). Clear out any debris, tree roots or old concrete that is in the way of the fresh concrete. Install the proper subfoundation of gravel and sand. Typically the sidewalk foundation will go down about six inches below the surface of the ground, but can be less in warmer climates or more in very frigid climates to allow for frost expansion.
- 2). Hammer stakes into the outside four corners of the slab site, leaving room for the inside planks. Run a string tight between the stakes on each side, tying it at each stake. Make sure the excavation is level with each side and the bottom is level. Hammer in wooden stakes that are at least one inch thick and about ten inches long every two feet. Their tops should be flush with the proposed top edge of the finished sidewalk.
- 3). Nail six inch planks sideways into the stakes from the inside, cutting them to measurements taken from the two sides of the slab. If you are replacing a section of slab, use a spacer between the old and new concrete to allow for expansion and contraction from fluctuating weather. For a whole new section of concrete sidewalk with many sections, allow a spacer between every section, equal to the width of the sidewalk.
- 4). Fill the molds with the concrete mixture, leveling it along the top of the wooden planks and stakes. Allow to cure for the recommended time and remove the wooden molds.
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