Photo: W.Carter
As sustainability and efficiency have become higher priorities for the construction industry, a material that’s been around since the 1950s has been surging in popularity.
Expanded polystyrene geofoam, or EPS geofoam, is a form of lightweight thermal plastic produced in sheets or large blocks. Since it first hit the market more than 60 years ago, it has been used primarily for filling voids in soil created during construction projects like highways, bridge embankments, and parking lots. Soil can be unpredictable and inconsistent, varying greatly in its composition from location to location. Geofoam acts as a lightweight base material, maintaining similar strength as soil while being just 1–2% as dense.
Surprises are definitely the last thing engineers want when stabilizing a steep slope or choosing a material for structural retention. Since it’s man-made, geofoam is highly consistent from batch to batch. It’s also highly insulative and will never break down and leech into the soil. In fact, it can even be dug up and used again. These are just some of the material’s advantages, which helps account for its expanding use in construction projects.
EPS Geofoam’s Infrastructure Roots
America’s infrastructure is dangerously underfunded, particularly its roads, bridges, and rails. A recent report by The Council on Foreign Relations (CFR) found that U.S. infrastructure faces a funding gap of more than $2 trillion. If not filled by 2025, it could mean potential serious safety concerns and billions in lost economic productivity.
According to CFR, there is hope that the Biden administration will put a greater emphasis on restoring America’s infrastructure, which would create nearly 2 million jobs over three years. Along with a greater investment in our nation’s infrastructure would come a major boom for construction companies contracted to do the work, which would need to be done quickly and efficiently to avoid disruption.
EPS geofoam has already proven its mettle under similar circumstances. Its usage in embankments for a major renovation of Interstate 15 in Utah back in 2002 earned the American Society of Civil Engineers’ Outstanding Civil Engineering Achievement award. Using synthetic materials like EPS geofoam enabled the project’s completion in just four years, half the time it would have taken using conventional methods, and $32 million under budget, according to For Construction Pros.
EPS geofoam not only allows for similar infrastructure projects to be completed faster and cheaper, but also there are additional savings that are realized over time as EPS geofoam needs virtually no maintenance compared to conventional materials and soil.
Geofoam Branches out Beyond its Supporting Role
EPS geofoam has a number of characteristics that make it as desirable for building applications as it’s been for roadways. As mentioned, it’s extremely lightweight and incredibly strong while remaining highly flexible so that it can be shaped as needed. This flexibility even allows it to help structures better withstand earthquake damage, as opposed to more rigid support materials like concrete that only strengthen a structure without helping dissipate the shockwaves, according to For Construction Pros.
It also plays nicely with traditional building materials like concrete, making it a perfect core material onto which concrete can be poured and cured. Its high customizability has proven useful in several recent projects that required strengthening a structure or adding elevation without increasing its weight. Geofoam International LLC recently spearheaded several such projects. The Monte Carlo Theater in Las Vegas used EPS geofoam blocks varying in size and thickness to build up its 5,000 capacity stadium seating. The Sonesta Hotel in Austin also used EPS geofoam cut to custom shape to reduce the weight of its pool deck.
EPS geofoam is also becoming a prized material in the accelerating green building movement. Its natural insulative properties and composition of up to 98% air make it a dependable thermal barrier that can serve as a durable and low-cost insulating material. Its small carbon footprint has made it popular in designs seeking LEED certification, which factors in materials used in construction as well as how efficiently a building operates once complete.
EPS geofoam is undergoing something of a renaissance in construction, moving well beyond its origins as a roadway filler material. Its low cost speaks for itself. However, its high strength, light weight, insulating properties, and ability to be cut to size to fit virtually anywhere make it a highly versatile material. Global Market Insights recently reported the global geofoam market is set to surge above $1 billion by 2026, and it’s easy to see why.
Urmila says
Great information on geofoam is having a moment in construction. Very Insightful.