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How to Make Your Own Concrete Stepping Stones

Part 2

Placing Stepping Stones

If you've made stepping stones to use as a footpath, some preparation is now needed before placing them in the ground.

First pace out the intended path, marking each footfall with a pebble.
Center a finished stone on the marked spot then sprinkle flour along the stone’s outside perimeter. Remove stone.
Dig down approximately 3-4" within the confines of the flour border, roughly leveling the bottom of the hole.
Pour 1-2" of sand into hole. Level sand.
Place the stepping stone. Jiggle back and forth until stone sits firmly and evenly in place. To set a stone higher or lower, simply add or subtract sand.

Concrete in Cold Climates

Special consideration needs to be given to the durability of stepping stones in cold climates. Concrete is porous; any water which has soaked into the stone will freeze and expand during cold winters, possibly creating fractures.

Some ways to prevent cracking are:

Concrete sealants:

Found in hardware and home improvement centers. They permeate the pores in concrete, helping form a water barrier. There are many sealants available on the market. Acrylic sealants are UV stable, inexpensive and easy to apply but have the softest, least durable finish. Solvent-based acrylic sealants generally perform better than water-based products for outdoors use, are UV-stable, and are recommended for applications where a flat finish is desired. Water-based epoxy bonds well to concrete, is harder than acrylic sealants, but isn't UV-stable. For stones containing iron oxide pigments, UV sealants will help maintain color.

Allow the stone to cure 10 days to 2 weeks before applying sealants. Concrete which has been completely painted with either concrete paint or patio paint need not be sealed.

Wire or nails:

Wire mesh (such as chicken wire) greatly improves concrete strength. Cut a sheet slightly smaller than the mold’s diameter, lay flat into mold half-filled with concrete, then fill mold to top. Another easy reinforcement is a couple handfuls of galvanized nails sprinkled into wet concrete as mold is being filled. Think of these as miniature rebar.

Welbond Universal Adhesive:

Weldbond brand can be found in hardware and home improvement centers. Mix 1 part Weldbond to 5 parts water; this will be approximately 4-5 ounces of Weldbond per stepping stone. Weldbond dramatically increases the strength of the concrete (up to 1700%).

Stepping Stone Mold Care

Your molds should last 10-20 pours, even more if given proper care. Here are some tips:

Do not lift filled molds while the concrete is still wet. Although the mold's rim can hold weight, repeated lifting will weaken the plastic. To move a filled mold, slide plywood underneath for easier transport.
Avoid vigorous tapping when removing air bubbles; this can cause cracks in the plastic. Should a crack develop in the mold, fill it with epoxy or Bondo, found at any hardware store. Apply these adhesives to the outer surface of the mold.
Store molds in a cool, dry place, away from heat and light. Heat makes all plastic brittle.

Create a plywood "sandwich." This technique will ensure the longest mold life possible by eliminating all stress on the plastic. To make a "sandwich," simply cut two 18" x 18" pieces of plywood (1/2" thickness is sufficient). Before filling mold with concrete, place one sheet of plywood underneath mold. When shaking out air bubbles, lift the edge of the wood (instead of mold lip) to vibrate the concrete. After curing, de-mold the stone by sandwiching mold between two sheets of plywood and flipping over.