If the weight of the finished stone is a consideration, the addition of perlite, pumice and peatmoss into a concrete mix reduces weight.
You can also add a styrofoam core without compromising the strength and durability of the stone. The procedure is simple.
Foam Core Stepping Stones
- Size a 1/2″ sheet of styrofoam to fit inside mold, leaving a minimum 1″ between inner wall of mold and circumference of styrofoam.
- Wrap styrofoam with a sheet of nylon fiber or wire mesh. This will help strengthen the finished stone.
- Fill mold with approximately 1/2″ – 3/4″ of concrete; tap lightly to remove air bubbles. Place styrofoam on top of concrete, then pour additional concrete to cover styrofoam. Fill to top, shake lightly to level concrete.
- To prevent styrofoam from floating to the surface, cover concrete with a sheet of plastic, then place a brick or stone in the middle of the mold. This will hold the foam in place.