Polyiso Impacts Are High, but Performance May Make Up for Them

One square foot of 3" thick polyisocyanurate (polyiso) insulation requires 15.22 MJ of energy to create, the equivalent of burning a little over a pound of coal. The same piece of rigid boardstock depletes 1.26 kg of non-renewable resources and uses 50 liters of water—adding up to a significant embodied footprint when spread over the surface of an entire building. That’s all according to an environmental product declaration (EPD) released by the Polyisocyanurate Insulation Manufacturers Association (PIMA).

The group has developed one industry-wide EPD for wall insulation and another for roof insulation, with both documents verified by NSF International. Third-party verification is required by the LEED v4 materials and resources credit relating to EPDs, as explained in Finding Products for LEED v4: A Guide.