When spray foam fails, it can fail spectacularly, so when selecting an insulation system for your new or renovated building here are a few points to ponder when wanting to minimise environmental impact while maximising energy performance and durability of the building.
With spray foam gaining popularity in Ontario in the last 10 years, it’s especially important to shed light on new technology and stated claims. The progressive builders and architects we work with want to ensure spray foam was installed properly and we often get called to test newly installed spray foam before the drywall goes on. Using methods described in ASTM E1186, we test the foam with Infrared and the blower door. On every job, we find significant air leaks unless the foam wasn’t part of the air barrier system.
This high-rise going up now on the south side of College Street, just west of Spadina Ave had it’s walls spray foamed. Gauging from the colour chart below, Demilec’s HEATLOK SOYA was used. It would have been inconceivable 10 years ago, but the popularity of spray foam grows in Canada.
So testing aside, once you decide on the application requirements for either half or two pound foam, the important issues to focus on when considering spray foam include – who will install it, what is the global warming potential and can the foam be made from more benign feed stocks of oil.
First and foremost, it’s critical to mention that spray foam is not the “silver bullet” often purported by the spray foam industry: yes, the installed product has amazing properties, but it’s only as good as the installer who’s responsible for manufacturing the foam on site. The expectations for this process are established in the CAN/ULC-S705 standards.
Unlike panels of extruded or expanded polystyrene that you can buy at the building supply store which are manufactured in a carefully controlled manufacturing facility, spray foam is not. Spray foam is manufactured in situ on the job site. For this reason you want the person pulling the trigger on the foam gun to know how to make good foam, when/where to install it and who will back all this up with documentation about the lot numbers of each barrel of foam used including test results for the foam density and adhesion to substrate. Get a referral for the individual pulling the trigger, not the brand of foam, not the company. They guy pulling the trigger is key.
The manufacturing of spray foam in situ takes an experienced hand; hire the person pulling the trigger. The ‘A’ side of the equation is a commoditised product and is generic to both low and medium density spray foams. The ‘B’ side is proprietary and many companies (see colour chart below) make their own formulations, but the bottom line is that the chemistry is very similar. Just like bread, it can look, smell and test different, but the basics ingredients are the same; flour, yeast, salt, water and heat.
Spray foam needs a “blowing agent” in order to make uniform foam that’s stable, with many, small, gas-filled closed-cells. Currently, the bowing agents used in almost all medium density – AKA “Two-pound” – foams are of a high Global Warming Potential (GWP) which as the foam ages, is released into the environment. So it’s exciting news that Honeywell introduced a new blowing agent called Solstice with a GWP of 1. The story gets better because Elastochem, based out of Brantford Ontario, is manufacturing their proprietary ‘B’ component called Insulathane Extreme and any spray foam company in Ontario can purchase and install this spray foam. The same equipment is used for all foams and there’s no reason for any contractor to not switch to this Canadian made product today.
The last point we want to consider when choosing insulation is “what’s the embodied energy” of the insulation. In other words, what’s the “heat, beat and treat” process for the harvesting of and transformation of raw ingredients? Because the ‘A’ component is the same for all spray foams, only the ‘B’ formulation can be tweaked.
A few spray foam manufacturers boast of using plant-based oils in thier ‘B’ side proprietary formulation sourced from soya or castor beans. The good news is that it keeps a few farmer’s employed, but the sad reality is that these plant-based oils often may account for only 10% to 20% of the total volume and because the industrial farming practices of growing plants use oil-based fertilizers, herbicides and pesticides the benefits are marginal at best.
The flowing links will lead you to two great documents that can help you prepare your job site for spray foam and better understand what the spray foamer needs to be thinking about.
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Prepping for Spray Foam – Green Building Advisor
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Guidance on Best Practices for the Installation of Spray Faom
Bottom line, when selecting spray foam, know the person who’ll be pulling the trigger on your job site, try to select a spray foam that has a low GWP and test your foam for air leakage before you pay the foam contractor – they often have to come back to fill low spots, missed spots and some rare cases repair off ratio foam. Spray foam can be great, but it can be very unforgiving if installed incorrectly.
