Carbon Smart Attributes for Insulation
Specify insulation materials that naturally sequester carbon
Materials such as wood, straw, clay-straw, hemp, cork, and sheep’s wool naturally sequester carbon and store if over their useful life. Using these materials can reduce the carbon footprint of your building.
Specify blown-in insulation instead of rigid and spray foams insulation
Blown-in fiberglass and cellulose insulation have a significantly lower embodied carbon impact than rigid insulation and spray foams. Also, if not properly installed (tacked to studs or rafters), some batt insulations can slump over time and spray foam can crack with building movement or settling, creating a thermal bridge and potentially leading to moisture condensation and wall assembly degradation. Using high density blown-in (non-foam) insulation (over 3.5 pcf) can help minimize thermal bridging, minimize embodied carbon, and improve the operational performance and lifespan of a building.
Avoid Expanded Polystyrene (EPS), Extruded Polystyrene (XPS), Polyisocyanurate (Polyiso), Structurally Insulated Panel Systems (SIPS) with foam insulation, and spray foam, where climate allows
All of the insulations listed above are petroleum-based products that require significant energy to manufacture resulting in a high-embodied carbon footprint. Where climate and project requirements allow, specify lower carbon alternatives.