Foam board and spray-foam (SPF) insulation products are growing in popularity due to their excellent insulating properties, but could these products be expanding your carbon footprint and exposing your family to dangerous disease-causing chemicals unnecessarily? This topic has been hotly debated in the building and environmental communities more and more of late, with compelling arguments offered from both sides of the aisles. But a proposed change suggested by green building experts could resolve the debate by making foam insulations healthier for you and the planet.
Let’s start by reviewing the two main concerns surrounding the use of foam insulation products:
- Blowing agents = big global warming impact: These substances, such as hydrofluorocarbon (HFC) blowing agents, which are used for extruded polystyrene (XPS) insulations such as Styrofoam (the blueboard) or Foamular (by Owens Corning, the pinkboard), are powerful greenhouse gases. When you compare different types of foam insulations, spray foams definitely have the more substantial impact. Contrast R-25 polyisocyanurate insulation, which “pays back” the global warming potential within 2.7 years, to XPS insulation, which requires a 36 to 65 year payback (depending on thickness), and you can see the clear winner. Spray foam insulations in particular are problematic for climate change.
- Added flame retardants = big health risks: For years, building codes have required that foam insulations be treated with flame retardance for fire resistance. The chemicals used – including HBCD (hexabromocyclododecane) for all polystyrene insulation and TCPP (Tris (1-chloro-2-propyl) phosphate) for polyisocyanurate insulation – are considered persistent organic pollutants (POPs), which means they bioaccumulate in the food chain, contributing to health problems such as reproductive, developmental, and neurological disorders. They can also pose threats to indoor air quality.
Obviously these are two serious downsides to the use of foam insulations. At least one of these may be easily solvable, according to a new advocacy group. For them, the most easily fixable problem with foam insulations is their use of flame retardants (FR). According to several studies, these insulations have been shown to offer no appreciable increase in fire resistance when they are not protected with a thermal barrier. When a thermal barrier, such as half-inch drywall, is added to the construction, fire protection increases noticeably. In other words, the thermal barrier helps prevent fires, not the chemicals.
The aim of the advocacy group is to change the building codes to allow FR-free insulations to be used under certain circumstances (small steps at first). For instance, in basements where the insulation is sandwiched between the earth and a thermal barrier, the risk of fire is very low, making it a very safe place to apply FR-free insulation. Eventually, the group would like to see the building codes adjusted to reflect the science by allowing foam insulations without FR to be used throughout a home if a thermal barrier is in place.
Until such time as these building codes are modified, if you’re concerned about your health or the environment, you may wish to consider alternatives to the foam insulations discussed above. BuildingGreen.com offers a great guide to insulation products you should definitely check out if you’re interested in learning more.