Definition. EPS is the least sustainable roof insulation in the study. Expanded polystyrene (EPS) has the worst environmental scores of the roof materials — a building performance of €0.095/m² per year and an Environmental Cost Indicator of €7.32/m² — at 11 kg CO₂-eq/m² and only 5% real reuse. It is a fossil material with no carbon storage.
Flax board scores best on the same roof. New Economy’s circular insulation study for Amsterdam reports this.
- EPS is the least sustainable roof insulation in the study