A New Era of High-Performance Buildings Demands Continuous Spray Foam Insulation
When it comes to building physics, we are seeing new techniques and technologies for the betterment of our planet, communities, and our people. Our understanding of how buildings live and function to suit our needs as it relates to energy efficiency, climate impact, and comfort revolve around air, temperature, and moisture. Just like the human race, scientific knowledge is ever-evolving, as does the way we design and build infrastructure. Many of our older buildings waste energy, provide poor indoor air quality, and (in terms of comfort level for the building occupants) rank high in distractions by poor lighting conditions, poor use of space, noise pollution, and uncomfortable temperatures. The “old way” of doing things is no longer the “good way” of doing things.
A building environment that fosters the well-being of our world and the people who reside and/or work in them can have a significant positive impact. There is a better way of building and retro-fitting for high-performance that delivers on superior efficiency, comfort, health and durability, and construct buildings that last and make our carbon footprint smaller.
Currently, buildings and homes contribute to approximately 17 per cent of Canada’s greenhouse gas emissions. Net-zero energy buildings are designed and constructed to produce at least as much energy as they consume on an annual basis.
A High-Performance Building Project Leads the Way
In June of 2020, Canada’s Minister of Natural Resources announced an investment toward the construction of an energy-efficient residential buildings project across Canada. Led by the Canadian Home Builders’ Association (CHBA) this project will see seven housing builders construct net-zero energy and net-zero ready residential buildings in British Columbia, Alberta, Saskatchewan, and Ontario. The project is looking to demonstrate it is possible to construct net-zero energy ready housing with reduced cost and construction time, which will in turn inspire energy-efficient changes throughout Canada’s construction industry.
This investment is part of the government’s bigger commitment to fight climate change, advance our clean energy future, and achieve net-zero emissions by 2050. A full $182 million in Federal funding is provided through Natural Resources Canada’s Green Infrastructure program to increase energy efficiency and address climate change by improving how our homes and buildings are designed, renovated, and constructed. A portion of the funding is going to support the development and implementation of building codes for existing buildings and new net-zero energy-ready buildings through various RD&D initiatives.
What Makes a High-Performance Building Perform?
From an energy performance standpoint, a high-performance building is addressed in Canada through a suite of green building certifications and rating systems, which include: BOMA BEST, BREEAM, BuiltGreen, EnerGuide, ENERGY STAR for New Homes, Green Globes, Green Key Eco-Rating Program, LEED, Living Building Challenge, Net Zero Home Labelling Program, Novoclimat, Passive House, Passive Solar Index, R-2000, SITES Rating System, TRUE Zero Waste, Zero Carbon Building Standard, Zero Energy Certification, and Zero Tool.
To meet the various building certifications and rating systems, the design and building community must first focus on the building envelope to control the transfer of heat and moisture throughout. This consists of the walls, roof, and foundation of the buildings they build. Things like fresh air intake via a balanced heat/energy recovery ventilation system that keeps catching the thermal energy of exhaust air and keeps that air inside the building. Also, high-calibre doors and windows that limit heat loss while allowing for daylight and passive solar energy, location factors that provide shading elements for the building and that protect from the sun when it’s not requires, airtight envelope, thermal bridge-free, and – of course – continuous insulation. Prioritizing the envelope as the first and foremost key high-performance building ingredient leads to reductions in energy demand to heat and cool the inside of the building. It’s amazing; passive house buildings reduce cooling and heating energy by 90 per cent.
When it comes to a high-performance build, we hear a lot about the ubiquity of the “all mighty” building envelope. It’s an absolute necessity to air leakage prevention and reducing energy loss inside. While being mandatory for passivity, it can also lead to the inability of moisture that occurs inside the home/building to escape. We all know what happens when moisture can’t escape; the enemy of all enemies starts to form: mould, mildew, and consequently unhealthy indoor air quality.
New Spray Foam Insulation Technologies Take Center Stage for Efficiency
To manage the moisture and prevent warm or cold inside air leakage, spray foam insulation companies have stepped it up with new closed-cell spray foam (ccSPF) hydrofluoroolefin (HFO) based technologies. Continuous insulation with no interruptions is essential for a high-performance building to perform well over time and not break down. The effect of thermal bridging has been neglected for years, now it’s taken into account with exterior insulation requirements being integrated with building codes. As demonstrated in the Building Envelope Thermal Bridging Guide Version 1.4, the cavity insulation can easily lose more than 50 per cent of its effectiveness when the structure thermal bridging impact is calculated.
This is why selecting the right assembly and choosing the right spray foam (SPF) is key as you will want to eliminate cold or hot spots throughout. You need an insulation with a high R-value, combined with no interruption from other building elements, and continuous insulation to remove/reduce thermal bridging.
There are many advantages to using ccSPF in your efforts for continuous insulation. First, not only can it reduce or remove thermal bridging, but it is also one of the highest R-value per inch of insulation products. It also acts as a water resistive barrier (rain screen), air barrier and vapour barrier. Second, continuous insulation reduces the chance of moisture damage, because water is unable to condense on the inside face of the sheathing. The more insulation is installed on the exterior of the structure, the lower condensation risks will be. Many buildings now use a complete exterior insulation: the perfect wall as Joe Lstiburek from Building Science Corporation would call it. The four control layers (water, air, vapour, and heat) are outside of the structure.
Keep in mind, however, that the continuity and durability of a ccSPF install depend both on the product you choose and the installer’s skills. It should only ever be installed by professionals trained by the manufacturer and its third party for their specific system. Some manufacturers have very strong technical support and can assist you with your technical questions, but also in finding a certified installer in your area.
Some ccSPF, like our own Huntsman Building Solutions Heatlok Soya HFO, have an R-value at R-6 per inch and also acts as the four control layers. It has the ability to expand and conform into the smallest crevasses and adhere to nearly all substrates regardless of shape and texture, making it ideal for areas which would nearly be impossible to insulate otherwise. These features mean a tight building envelope and the prevention of mould and condensation for an altogether better indoor air quality.
Air barrier solutions should be tested as systems to ASTM E2357, “Standard Test Method for Determining Air Leakage Rate of Air Barrier Assemblies.” Other types of insulation must often use tape or full surface membranes to meet this requirement. ccSPF is commonly used as an insulating air barrier system in commercial construction. It has been tested as an air barrier system and gone through an additional durability test procedure to confirm its air barrier system test compliance after a full year of exposure to the Canadian climate. Heatlok Soya HFO is currently under testing to transition the previous Air Barrier System to the new HFO product.
Great for High-Performance Buildings and Better for the Environment
“What’s good for the goose (high performance buildings), is good for the gander (the environment)”. Today’s better designed ccSPF technologies are not only high-performance building winners but act as an ultra-low global warming potential (GWP) insulation with superior spray-ability, adhesion, and compressive strength. They meet compliancy with the Paris Agreement, the Kyoto and Montreal Protocols, and have GWP 1 ratings, which is 99.9 per cent lower than traditional blowing agents, and contain a total of 22 per cent recycled plastic and renewable soya oil content. With Heatlok Soya HFO, just one of our resin drums contains up to 3,000 plastic bottles that are diverted from landfills. Spray foam insulation with new lower emissions blowing agents is more sustainable than ever.
A Close-Knit Family is a Healthy Family
High-performance buildings are full of complexities. They are more than just orientation, climate friendly, responsive to R-values, efficient in terms of mechanical systems, provide healthy indoor air and glazing that effectively balances daylight and heat gain. All these members (along with the siblings that lie beneath, including ccSPF) form a strong and united family. In this case, a healthy and efficient building.
Who wouldn’t want to live in a building where the temperatures are steady in every room, where there is no air leakage or water infiltration, where the air quality is good, where there isn’t any condensation or mould, where the floors are warm, where we light a fire for the ambiance and not for the heat it produces, and where the heating costs are close to nothing? High-performance buildings can make you achieve all of this. Many programs, listed previously, can guide you in designing or building high energy efficient buildings. It costs nothing to ask and can make you save a lot. It is not as complicated as it may sound and is actually pretty simple. Many building envelope product manufacturers also have solutions available for you to get there.
About the Author
Maxime Duzyk is the director of building science and engineering, North America with Huntsman Building Solutions. He’s been in the spray foam insulation business for the last ten years.