EPS Geofoam is used in most new swimming pool construction projects and renovation projects. For this renovation project in Washington, DC, the contractor used 2” thick sheets of EPS22 Geofoam. One of the objectives of the renovation was to reduce the depth of the deep end of the pool by approximately 48 inches. Using EPS Geofoam, weighing just 1.35 pounds per cubic foot instead of sand or gravel weighing 140 to 150 pounds per cubic foot, the contractor was also able to reduce the dead load on the bottom of the pool instead of increasing it. Using EPS instead of other fill material eliminated about 560 pounds per square foot. Since 4 foot of water weighing 60 pounds per cubic foot was also replaced by the Geofoam, it saved another 234 pounds per square foot of pressure on the bottom slab for a total of just under 800 pounds per square foot.
EPS Geofoam is available in sheets, blocks, shapes and tapered pieces. Large volume pool contractors seem to prefer working with 2” sheets because they install quickly and if material is left over it just moves on to the next project, creating very little waste. Precut blocks and tapered pieces can be used also but the contractor will spend more time looking for particular pieces that goes in a particular spots, like working on a very large puzzle where all of the pieces are white. For some projects, a combination of precut blocks or shapes along with stock sheets make the most sense.
EPS is easily cut with a hot knife or hot wire cutter. These tools are specifically designed to cut EPS and do it cleanly and quietly. Electric hot knives are available with up to 10” long blades and the standard Geofoam hotwire kit will cut over 100” block of EPS.