But SPF is still a plastic, right? Cumulatively, one can make a case for the contribution spray
foam makes to an enhanced energy efficient design. As the demand for energy efficiency grows
– either by building owners who want to conserve energy or by regulatory agencies that what to
reduce CO2 emissions, spray foam’s ability to provide greater thermal resistance and superior air
barrier performance will ensure increased use of the product. But is that enough for spray foam
to be considered a green building product? Probably; afterall, all insulation materials save more
energy than the use during manufacture. However, SPF remains a plastic. Energy efficiency is
only part of the equation in appropriate environmental design. There is also the issue of material
impact. Off-gassing, VOC emissions, non-degradable waste, and design durability are equally
important. And here, one might suspect that SPF would fail.
When considering recent product developments in the SPF industry, the answer becomes
obvious. To comply with the Montreal Protocol, the spray foam industry was forced to find safer,
environmentally friendly material components. The research and product development is now
complete—at present, SPF materials are a Zero Ozone Depleting Substance (Zero ODP). Further,
the recent introduction of a new generation of blowing agent, Hydrofluoroolefin, has had a
profound impact on the spray foam market. Closed cell, medium density spray foam products
now have minimal Global Warming Potential – an industry-wide GWP of less than five.
The SPF industry has become committed to environmentally responsible products. Spray foam
raw materials are currently produced with a higher content of rapidly renewable substances –
lavender oils, vegetable oils and rainwater. SPF products have significantly reduced the use of
virgin raw materials and replaced those components with elements made from recycled plastics
(PET) and plant-based oils. The commitment to recycled content is significant. The discerning
designer can now readily locate spray foam products that make a contribution to certified ‘Green’
building strategies (especially LEED).
The insulation industry in general, and the foam insulation market in particular, received ‘the
guilt-by-association’ effect of the urea formaldehyde (UFFI) ban. UFFI’s possible ‘off-gassing’ was
determined to create a potential health risk. And even though most of today’s data would
indicate an overreaction occurred, the effects of the UFFI ban linger on for foam insulations(4)
SPF is formaldehyde-free and has never experienced ‘offgassing’. Within 24 hours of site
manufacturer, the SPF is 1/100 of the allowable limit for Volatile Organic Compounds (VOCs).
Only during the application process does one need to be concerned about VOCs, and even then,
at distances of greater than ten metres, the effects are negligible. SPF, when installed by
trained, certified and licensed installers,(5) is a safe and environmentally friendly product. In fact,
SPF can be a contributor to LEED’s ‘Low-Emitting Materials’ credit when used as a Sealant
(conforms to SCAQMD Rule #1168).
So, SPF contributes to several LEED credits – Energy & Atmosphere (energy performance),
Materials & Resources (recycled content), and Indoor Environmental Quality (low-emitting
materials). But what about the undeniable fact that SPF is a plastic product and that plastics are
not biodegradable? SPF, when discarded lays inert with other non-biodegradable products for
relative eternity—true and undeniable. However, consider that the SPF application, by definition,
is customized at the jobsite. The actual waste generated is considerably less than factory
manufactured insulation products that are cut to fit at the jobsite. Here is where most
environmentalists agree that choosing the benefits of an energy efficient product that solves a
multitude of efficiency design situations, outweighs the minimal downside of the product.
And the product’s endless longevity is consistent with another cornerstone of environmental
design – durability. For the same reasons that SPF does not deteriorate in the landfill, the
product remains constant in the wall assembly, outlasting even the most ambitious design
projections. SPF’s moisture management is the key. First, the product resists moisture
migration. Second, any moisture that does penetrate the insulation dries within typical
temperature cycles exclusive of any deterioration of SPF’s thermal resistance(6).
In short, SPF can provide the water resistive barrier, the air barrier, the thermal barrier and the
vapour barrier functions all in one easy and single application to the building envelope,
eliminating the need for a multi-layer application
Can a plastic considered a green building product? If the product contributes to elevated energy
conservation, is a zero ozone depleting substance, has a minimal GWP, and is manufactured with
a high recycled content, it is worth considering the benefits. Further, more efficiency in less
space contributes to developmental density. SPF’s superior resistance to vapour diffusion
contributes to combating the effects of making a building tight; and, the multi-faceted properties
of SPF (insulation/air barrier/vapour retarder) produce obvious economies of scale and allow the
design professional the opportunity to participate in elevated energy efficiency design. Today the
public is ‘consumered’ with the idea of ‘going green’— SPF is a real option in making momentum
Mike Richmond, [email protected]
Mike Richmond is employed by Genyk Polyurethanes as a Building Science Specialist. He is a LEED
Accredited Professional and a Building Science Specialist of Ontario as sanctioned by the Ontario Building Envelope Council.
(1). The most popular air barrier membrane has achieved a rating of 0.005 L/s.m2 air leakage when tested using ASTM E283. Under the same conditions, SPF achieved an average 0.00014 L/s.m2 rating.
(2). SPF Outperforms Fiberglas in Attic Insulation Performance Tests at Oak Ridge National Laboratories,
(3). G.Finch, & Dr. J. Straube, “Field Performance of Spray Polyurethane Foam: The Role of Vapour
Diffusion Control”, April 2007.
(4).Subsequent studies and failed court cases have established the overreaction to UFFI.
(5). Spray foam installers are obligated to conform to the conditions of a stringent Quality Assurance Program.
Obligations include Installer training, inspection and certification as well as random and mandatory 3rd
(6). G.Finch, & Dr. J. Straube, “Field Performance of Spray Polyurethane Foam: The Role of Vapour
Diffusion Control”, April 2007.