The Passive House Institute U.S. (PHI) no longer grants certification approval for construction projects using SPF insulation, which employ chemical agents with high Global-Warming-Costs (GWP). PHIUS’s executive director Katrin Klingenberg explained the decision:
“It does not make any sense at all to use them if one of the major overarching goals of energy conservation in buildings is to counteract and decrease global warming and climate change,” Katrin Klingenberg told EBN. “There really is no point to go through all the trouble of detailed Passive House design calculations if you use high-GWP spray foam.”
Cellulose insulation has the lowest embodied energy among the leading types of insulation: Cellulose takes less energy to make than any other leading insulation material. Fiberglass has up to 10 times more embodied energy than Cellulose, and spray polyurethane foam insulation (SPF) products have up to 64 times more embodied energy than that of Cellulose.
The basic function of insulation is to save energy. However, as concerns about climate change continue, focus on the global warming impacts of insulation, and likely all building materials, can be expected to grow. As time goes on and demand for environmentally preferable building material continues to rise, there will undoubtedly be more emphasis on GWP.
Cellulose insulation is at the forefront of green-construction innovation by default. At up to 85% recycled content, most of it post consumer waste paper, Cellulose insulation is by design Eco-friendly. Add to that extremely low embodied energy and it also has a very low GWP. Many homebuilders and architects are specifying cellulose as the insulation of choice for building greener homes.
The Passive House Institute U.S. focuses on energy performance, and as one of the sole industry rating standards to do so, it is highly regarded. Their move to ban SPFs signifies the ever increasing standards of new building construction, and it reinforces the importance of considering embodied energy of insulation products and all the components of construction in the continuing evolution of green building. It will be interesting to see if other energy-efficiency and green building bodies follow with more emphasis on embodied energy.