Checklist of Recommendations for Reducing Impacts of Polystyrene
As long as doing so will not compromise energy performance of a building, seek alternatives to XPS and EPS. In some places there may be no alternative.
Contact XPS and EPS manufacturers about HBCD-free products
Try to convince manufacturers to shift to safer flame retardants. Until such products become available, ask manufacturers to introduce non-flame-retardant XPS and EPS that is labeled for below-grade applications only.
Specify rigid mineral wool for below-grade exterior foundation insulation
Along with being free of flame retardants, rigid mineral wool offers superb drainage and is resistant to termites and carpenter ants.
Consider interior foundation insulation
XPS and EPS can be avoided on foundation walls by moving the insulation to the interior, where less moisture-resistant insulation can be used, such as polyisocyanurate, fiberglass, and cellulose.
Specify SPF or rigid mineral wool beneath slabs
High-density spray polyurethane foam (SPF) is acceptable as a sub-slab insulation material. Rigid mineral wool is also used in this application in Europe, and could become accepted here.
Look for SIPs, ICFs, and EIFS made with rigid mineral wool
Such products are not known to be available today, but could be excellent products were manufacturers to introduce them. Talk to manufacturers and let them know you would be interested in such products.
Convince rigid mineral wool manufacturers to switch to non-formaldehyde binders
Rigid mineral wool today is produced with urea-extended phenol-formaldehyde binder. Converting to a non-formaldehyde binder would result in a greener product.
Do not sacrifice energy performance in seeking to avoid flame retardants
While brominated flame retardants, including HBCD, are believed to be harmful to human health and the environment, failing to achieve very high levels of energy performance contributes to climate change. If you avoid XPS or EPS is avoided due to health or environmental concerns, switch to an option that offers equally good or better energy performance.
