EPS vs GPS — You’ve Got Options

Greenstone Building Products offers two selections for the ICE Panel core. Our standard offering being Expanded Polystyrene (EPS) and a premium option – Graphite Polystyrene (GPS).

Expanded Polystyrene (EPS) and Graphite Polystyrene (GPS) are Type 2 EPS options available for the core of the ICE Panel. Both options offer identical structural capacity (flexural strength minimums, compressive strength minimums, and density targets). This is set by the CAN/ULC S701.1 standard for EPS insulation.

The graphite does not change the burning behavior or finished foam density. As such, the fire-resistance rating, flame spread/smoke developed index, STC rating, and water vapour permeance remain the same.

What’s The Difference?

Other than the difference in color of the resin bead, the main difference is the superior R-values offered by the GPS option. GPS includes graphite which increases the emissivity of the EPS over standard white EPS, making it more energy efficient. See the comparison chart below for reference.

Insulated Composite Envelope (ICE)

The Insulated Composite Envelope (ICE) is an engineered combination of EPS and galvanized steel – two well known and accepted building materials. Its performance far exceeds what each component could achieve on its own. This combination results in a much lighter and stronger building envelope. The ICE Panel has impressive transverse and compression bearing capacities. The unique manufacturing process and connection details eliminate thermal bridging, making it the most efficient building envelope available on the market.

Expanded Polystyrene (EPS and GPS)

EPS is a rigid cellular plastic that is up to 97% atmospheric air. EPS has no trapped gases which create inflated R-values; this means no toxic off-gassing and a maintained R-value.

GPS is expanded polystyrene that is infused with graphite, which increases the emissivity of the EPS over standard white EPS, making it more energy efficient. ICE Panels produced with a GPS core will be gray/platinum in color, and other than this color variation, the main difference is the superior R-values offered by the GPS option.

Galvanized Steel

Galvanized steel has a high strength to volume ratio, which makes it ideal for versatile designs. It is environmentally stable, completely recyclable and has a 200+ year life expectancy.