There’s Only One Styrofoam^™ (and it’s not a cup)

When people hear the word “Styrofoam,” they often think of foam cups, fast food containers or packaging. But construction professionals know better. Unlike the expanded polystyrene (EPS) foam that’s used to make disposable containers, DuPont™ Styrofoam™ Brand Extruded Polystyrene (XPS) Insulation is a high-performance, closed cell foam used to insulate homes and buildings. That closed cell structure is what gives Styrofoam™ Brand the thermal protection and moisture resistance that help buildings stay warm in the winter, cool in the summer and dry year-round.

What is ‘closed cell’ foam? If you look under a microscope at the white EPS foam you know as disposable cups, coolers and packaging, you’ll see gaps between the foam cells. Over time, those gaps let in air and moisture. Those gaps also reduce the material’s compression strength. Ever crushed a foam cup in your hand? That’s low compression strength! However, if you look at Styrofoam™ Brand XPS Insulation under a microscope, you won’t see those gaps. It’s a closed cell foam that provides exceptional thermal, moisture and air protection for homes and buildings. It also has great compression strength, so it can withstand the demands of a tough jobsite, last for decades and even be reused when buildings are remodeled!

Now that you know there’s only one Styrofoam™ Brand – and it’s not a cup – what should you call those white foam cups, containers, coolers and packages? EPS, polystyrene or foam are all accurate terms to describe EPS material. Styrofoam™ is an entirely different material – a rigid board insulation invented in 1941, trademarked and, until a major reformulation in late 2023, known for its distinctive blue color. The newest generation of Styrofoam™ Brand XPS is now produced in grey, signifying its low global warming potential formulation.