< PreviousBuilding Science Association of Ontario11 UP FRONT T he Ontario Building Envelope Council (OBEC) is excited to announce its rebranding as the Building Science Associ- ation of Ontario (BSAO). This change reflects our ongoing commitment to advancing the field of building science and our dedication to meeting the volving needs of our industry. The decision to rebrand comes as part of our strategic initiative to better represent our mission and broaden our outreach to pro- fessionals involved in building science. The new name emphasizes our focus on education, research, and collaboration among archi- tects, engineers, contractors, manufacturers, and researchers. “Our rebranding to the Building Science Association of Ontario signifies our dedication to advocating for building science and pro- vide quality education and forums for collaboration for members to network and increase their technical knowledge,” said Daniel Aleksov, President of BSAO. “We believe the new name captures the essence of our mission and our commitment to sustainability and performance in the built environment.” BSAO will continue to provide valuable resources, education- al programs, and networking opportunities to its members while championing the importance of building science in addressing today’s challenges in construction and sustainability. We invite all stakeholders in the building industry to join us on this exciting journey as we work together to enhance building performance and ensure a sustainable future for Ontario. We will be updating all OBEC branding to align with the new BSAO branding, including across this issue of Pushing the Envel- ope Canada. You’ll notice this change occurring in phases. Our new website, www.bsao.ca, will be launched soon. In the meantime, once it goes live, you will be automatically redirected from the cur- rent www.obec.on.ca site to the new site. We are excited about this new direction and look forward to the future of BSAO. If you have any questions, don’t hesitate to contact the BSAO, Operations Manager, Sherry Denesha, at info@bsao.ca. Ontario Building Envelope Council Rebrands as Building Science Association of Ontario! BUILDING ENVELOPE SYSTEMS EXAM Date Friday, May 9, 2025 Location •Markham, ON: BSSB Office, 2800 - 14th Ave., Suite 210, Markham, ON L3R 0E4 (1:00 pm - 5:00 pm ET). •Kitchener-Waterloo area: EXP, 405 Maple Grove Road, Suite 6, Cambridge ON (1:00 pm - 5:00 pm ET). •Ottawa area: Cleland Jardine, 580 Terry Fox Drive, Suite 200, Kanata ON (1:00 pm - 5:00 pm ET). •Edmonton, AB: Entuitive - 10055 106 Street NW, Suite 650, Edmonton, AB (9:00 am – 1:00 pm MT). MATERIALS EXAM & MECHANICAL SYSTEMS EXAM Date Friday, October 17, 2025 Locations •Markham, ON: BSSB Office, 2800 - 14th Ave., Suite 210, Markham, ON L3R 0E4 (1:00 pm - 5:00 pm ET). •Kitchener-Waterloo area: EXP, 405 Maple Grove Road, Suite 6, Cambridge ON (1:00 pm - 5:00 pm ET). •Ottawa area: Cleland Jardine, 580 Terry Fox Drive, Suite 200, Kanata ON (1:00 pm - 5:00 pm ET). •Edmonton, AB: Entuitive - 10055 106 Street NW, Suite 650, Edmonton, AB (9:00 am – 1:00 pm MT). UPCOMING BUILDING SCIENCE SPECIALIST EXAMS T he Building Science Specialist (BSS) designation recognizes those who meet the strict educational and practical requirements set forth by the BSS Board of Canada (BSSB). This designation has become the benchmark qualification of Building Science practi- tioners and provides members of the industry, including building designers, specifiers, developers, contractors, and owners, the confidence that any designation holder has a high level of education and understanding in the field of Building Science as deemed by the BSS Advisory Committee, composed of key industry figures. Register today here: https://bssb.ca/bss-exam/bss-exam-application-2.Building Science Association of Ontario13 FEATURE By Christine Asfour-Meta, Durabond Products Limited Best Practices for Constructing a Building Clad with EIFS: Ensuring Durability, Thermal Benefits, and Long-Term Performance T he building envelope plays an es- sential role in modern construc- tion, serving as the primary barrier against environmental elements while en- hancing energy efficiency, aesthetics, and durability. Exterior insulation and finish systems (EIFS) are highly effective, providing thermal insulation, flexibility, and moisture control. However, performance depends on proper installation, especially at interfaces, terminations, and impact-prone areas. This article outlines best practices for EIFS-clad envelopes, highlighting thermal benefits, precise detailing, and impact re- sistance to ensure durability. It also reviews insulation materials’ properties and limit- ations in meeting performance and code requirements. UNDERSTANDING THE THERMAL BENEFITS OF EIFS ENERGY EFFICIENCY One of the primary advantages of EIFS is its thermal performance. EIFS typically uses insulation boards applied to the ex- terior wall surface. This continuous layer of insulation reduces thermal bridging, a com- mon issue in traditional construction where heat escapes through structural elements such as studs, resulting in energy loss. •Continuous insulation (C.I.): By placing the insulation on the exterior of the building, EIFS provides an uninterrupt- ed thermal barrier (C.I.), reducing heat loss in the winter and keeping interiors cooler in the summer. This can contrib- ute to lowering the operational carbon footprint of the building. The effect- iveness and value of the C.I. of EIFS is Figure 1: Halo Towers project thermographic IR scans. Photos courtesy of Christine Asfour-Meta.14Pushing the Envelope Canada• Spring 2025 FEATURE displayed by the Thermographic Imaging of the Halo Towers buildings in Winnipeg Manitoba (Refer to Figure 1). The thermo- graphic (IR) scans were conducted during a Winnipeg winter evening with temper- atures averaging at -20°C, yet the thermal scans of the façade clearly display a con- tinuous uniform uninterrupted thermal layer broken only by fenestration and/or exhaust vents. •R-value optimization: EIFS offers the flexibility to achieve a high R-value de- pending on the type and thickness of the insulation board used. Architects and builders can tailor the system to meet or exceed local energy code re- quirements. Designers are increasingly selecting an exterior envelope utilizing EIFS with all the thermal resistance on the exterior of the sheathing and leaving the cavity free for other utilities installa- tions, a most effective way to maximize thermal efficiency, as displayed by the thermal scans in Figure 1. INSULATION TYPES IN EIFS The choice of insulation material signifi- cantly influences the thermal and fire per- formance of EIFS systems: 1.Expanded polystyrene type 1 (EPS): EPS is the most common insulation material used in EIFS due to its cost-effective- ness and excellent thermal perform- ance. EPS thickness is generally limited to a maximum of six inches (152 mm) based on fire testing performed by specific manufacturers. Always confirm allowable thickness by reviewing the manufacturer’s fire test data. EIFS util- izing expanded polystyrene (EPS) intended for use in buildings required to be of non-combustible construction may not be permissible unless proven in compliance with Article 3.1.5.5 of the National Building Code of Canada and/ or applicable code requirements. In such cases, EIFS utilizing EPS tested to CAN/ ULC-S134 may be utilized, provided that there are no additional spatial separation constraints, and the applicable codes section allows for more than 10 per cent unprotected openings on the exposing building face. For case specific, it is rec- ommended to consult with the EIFS manufacturer and the Authority Having Jurisdiction (AHJ) on the project. 2.Semi-rigid mineral fiber: EIFS systems utilizing this type of insulation boards are classified as 100 per cent non-com- bustible cladding, which while it comes at a higher cost, offers several benefits and solutions. Being non-combustible, it offers a higher level of safety and solu- tions in areas where code spatial sep- aration restrictions allow less than 10 per cent unprotected openings. Addi- tional considerations in the use of these systems should include overall cost, method of attachment and overall system weight. While thickness- es greater than six inches (152mm) are theoretically possible, most applications are also limited to six inches due to prac- tical considerations. 3.Higher thermal resistance insulation boards: There are several different types of insulation boards which offer higher thermal resistance per thickness than the standard EPS. Most common are higher density EPS (Type 2 or 3), extruded poly- styrene (XPS), specialty insulation boards such as graphite and others. Each of these offer higher thermal resistance properties than standard EPS, but they come at a higher cost. These are often used in projects requiring enhanced thermal performance within specific design constraints. Recommended to consult with the EIFS manufacturer spe- cifics as the systems offered may differ in components and composition. MOISTURE CONTROL Another key benefit of EIFS is its ability to manage moisture. Modern EIFS systems are typically designed with an integrated drainage layer, referred to as Geometrically Defined Drainage Cavity (GDDC), that al- lows water to escape, preventing moisture from being trapped behind the system and causing damage to the substrate. Halo Towers project in Winnipeg, Manitoba.Building Science Association of Ontario15 IMPLEMENTING ACCURACY IN EIFS INTERFACES AND TERMINATIONS EIFS provides excellent thermal and moisture management, but its long-term performance depends on precise installa- tion, particularly at interfaces and termin- ations where building components con- verge. Poor transitions can lead to water infiltration, thermal bridging, and reduced performance, making attention to details critical for long-term durability. KEY FOCUS AREAS: •Continuity at secondary barrier: Ensure a continuous tie-in between the EIFS water-resistive barrier (WRB) and adjacent components like window mullions, door frames, and penetrations. This prevents moisture intrusion and ensures incident- al water is drained outward. •Fenestration openings: Seal and flash window heads and sills effectively. Use a two-stage sealant approach with backer rods, sealants, and flashings to protect against moisture and air leakage. •Roof-to-wall connections: Roof-wall interfaces require precise transition flashings and termination bars for a con- tinuous barrier. Use kick-out flashing to divert moisture outward in high-expos- ure areas. •Expansion and control joints: Properly spaced and sealed joints accommodate building movement, preventing cracks or separation. Include a two-stage seal with a WRB back seal and vented front seal. •Termination at grade: Detail the bottom edge of the EIFS, four to eight inches above grade, with horizontal weep mechanisms to divert moisture. Seal any joints below this level continuously to prevent water intrusion. ENHANCING DURABILITY WITH HIGH IMPACT RESISTANCE While EIFS provides excellent thermal and moisture performance, it is inherently more vulnerable to impact damage than traditional cladding systems like brick or concrete. Enhancing impact resistance is essential in high-traffic or impact-prone areas to preserve the system’s long-term integrity. BEST PRACTICES FOR INCREASING IMPACT RESISTANCE •Double-layer reinforcement: In high-impact areas, such as near the ground level, using a double layer of reinforcing mesh within the base coat significantly improves resistance to impact damage. •High-impact mesh options: Stronger and denser than standard mesh, high-impact mesh is ideal for use in com- mercial buildings, schools, and other public structures. Applying multiple layers of high-impact mesh substan- tially improves resistance to damage resulting from heavier impact, which brings EIFS performance closer or equal to the more traditional hard services. •Protective coatings: Durable topcoats with enhanced resistance to scratching, abrasion, and environmental wear can help maintain the EIFS appearance and performance over time. Features such as hydrophobic finish coatings. EXTENDING THE LIFE CYCLE AND PERFORMANCE OF EIFS To fully realize the benefits of EIFS, building owners and managers must pri- oritize routine maintenance and periodic inspections. Proper care ensures the EIFS continues to perform as intended through- out its life cycle. MAINTENANCE BEST PRACTICES: •Regular inspections: Focus on critical areas such as sealants around windows, terminations at roof and grade level, and any signs of impact damage. Early detection of issues allows for cost-ef- fective repairs. •Cleaning: Routine cleaning prevents the buildup of dirt, mold, or algae on the EIFS surface, protecting its aesthetics and finish durability. •Prompt repairs: Address any impact damage, cracks, or punctures immedi- ately to prevent water infiltration and maintain the thermal barrier’s integrity. CONCLUSION EIFS is a versatile and effective clad- ding system that offers superior thermal performance, moisture control, and de- sign flexibility, making it an ideal choice for modern construction. Understanding the properties and limitations of insulation ma- terials and focusing on accurate interface and termination details are essential for optimizing system performance. Further- more, improving impact resistance in high- risk areas, and ensuring consistent main- tenance throughout the system’s lifecycle are critical for prolonging the durability and performance of EIFS. This ensures a build- ing envelope that provides long-lasting protection, energy efficiency, and aesthetic appeal, even in the face of evolving environ- mental and regulatory challenges. ■ Christine Asfour-Meta is a Building Envelope Consul- tant at Durabond Products Limited, with over sixteen years of experience. She has held senior roles in design and project management, specializing in prefabricated EIFS panels. As a Building Envelope Consultant, she shares her expertise of EIFS best practices with designers, contractors, and applicators. FEATURE16Pushing the Envelope Canada• Spring 2025 FEATURE By Helen Stopps, Maria Milan, and Odel Linetska, Toronto Metropolitan University; Sarah R. Haines, University of Toronto; Natalie Clyke, From Harvest to House; and Becky Big Canoe, Mno Aki Land Trust Exploring Pathways to Improved Housing in First Nations Communities A cross Canada, there is a widespread housing and infrastructure crisis on First Nations reserves, including a lack of available units, severe overcrowding, unaffordable prices, and inadequate housing conditions. 1 This housing crisis is deeply rooted in the legacy of colonialism, which has led to the widespread disruption of First Nations homemaking through interrelated processes including: the displacement of communities from ancestral home- lands, the separation of families, and the imposition of Western ideologies and organizational structures. 2 Housing is widely recognized as a key social determinant of health, and the housing crisis on many reserves has been recognized as a major contributor to long standing health and socioeconomic inequities. 1 Despite decades of government re- ports, academic literature, and statements from reserves acknowledging the housing crisis, little has changed. The March 2024 Auditor General’s report highlighted that, despite two decades of efforts, significant gaps in housing persist, with 80 per cent of the needs identified by the Assembly of First Nations in 2021 still unmet, making the 2030 deadline to address the hous- ing deficit increasingly unattainable. 3 Ad- dressing on-reserve housing challenges is a complex issue influenced by historical injustices, systemic barriers, and logistic- al difficulties. This article aims to break down these challenges in an accessible way, providing policymakers, profession- als, and everyday Canadians with a clear- er understanding of the factors shaping housing efforts and potential solutions, drawing from our recent academic paper “Ten questions concerning First Nations on-reserve housing in Canada,” written in partnership by First Nations housing leaders and researchers from Toronto Metropolitan University and University of Toronto. 4 HOW DOES ON-RESERVE HOUSING DIFFER FROM OTHER HOUSING IN CANADA? On-reserve housing is fundamentally different from other housing in Canada due to legal, economic, structural, and funding challenges. The Canadian federal Snowy roads on-reserve in Saskatchewan. Photos courtesy of Sarah Haines.Building Science Association of Ontario17 FEATURE government primarily acts as the funder for on-reserve housing and First Nations governments manage the development, allocation, and maintenance of on-re- serve housing decisions on behalf of their communities. Unlike off-reserve housing, which is subject to municipal and provin- cial regulations, on-reserve housing falls under federal jurisdiction as part of the Canadian federal government’s fiduciary responsibility to Indigenous peoples. As such, on-reserve housing is often exempt from national building codes unless speci- fied by funding agreements. This creates inconsistencies in construction quality and enforcement. Additionally, land ownership on re- serves is communal under the Indian Act, preventing individuals from using land as collateral for mortgages, which significant- ly limits homeownership opportunities and private investment in housing. 5 As a result, the majority of on-reserve hous- ing is band-owned, meaning that housing decisions, funding allocations, and main- tenance responsibilities fall largely under the governance of the band council rather than individual homeowners. On-reserve housing is primarily fund- ed by federal programs administered by Indigenous Services Canada (ISC) and the Canada Mortgage and Housing Corpor- ation (CMHC). Funding models are highly fragmented and characterized by short- term, proposal-based allocations, which creates significant barriers to long-term housing planning and infrastructure in- vestment. Proposal-based funding can also unintentionally reinforce disparities between communities. Those with more administrative capacity and well-de- veloped funding applications are more likely to secure financial support, while communities with the greatest housing need often lack the capacity to prepare ‘shovel-ready’ projects and are thus left underfunded. 3 BARRIERS TO IMPROVING ON- RESERVE HOUSING Historical underfunding, governance constraints, infrastructure limitations, and restrictive land policies all present challen- ges which impact housing availability and quality on reserve. In many communities, a lack of skilled tradespeople, geograph- ic remoteness affecting material supply chains, and ongoing maintenance deficits compound these structural challenges. Additionally, the absence of self-deter- mined housing policies restricts First Na- tions’ ability to implement long-term hous- ing strategies tailored to their needs. Many homes on reserves were (and still are) built using standardized designs that prioritize cost-efficiency over cultur- al relevance, often lacking features such as large communal areas or appropriate ventilation for cooking or high occupancy loads. Housing that does not align with cultural and community needs can con- tribute to social stress, limit traditional practices, and result in early deterioration of the building envelope. Further, barriers to improving on-re- serve housing are not isolated issues but rather the result of interconnected systemic barriers, where feedback loops reinforce existing challenges, making housing improvements difficult to sustain without systemic intervention. One key ex- ample is the cyclical relationship between housing availability and quality, funding availability, and administrative capacity. A lack of available housing units contrib- utes to overcrowding, which accelerates deterioration and increases maintenance requirements. This ultimately reduces the number of available units due to severe degradation or the need to divert funding away from new construction to mainten- ance needs, perpetuating a cycle where housing availability and quality continues to decline. In turn, deteriorating hous- ing conditions may further strain limited administrative resources to obtain more funds through proposal-based funding structures, creating a cycle where under- funded communities struggle to maintain and expand their housing stock. Without structural reforms that prioritize self-de- termined, stable investment approaches, these systemic issues will continue to limit housing improvements on-reserve. HOW DO WE MOVE FORWARD? To improve housing on reserves, place- based solutions that embrace local cul- ture, climate, and geography are essential. Construction begins on new on-reserve housing.18Pushing the Envelope Canada• Spring 2025 FEATURE These solutions must emphasize co-de- velopment by community members, build- ing scientists, engineers, and policymakers, ensuring that both technical expertise and policy frameworks align with community needs and priorities. While this is not yet the norm, many First Nations initiatives have already demonstrated innovative approaches that successfully integrate cul- tural and environmental considerations while addressing systemic challenges. In British Columbia, the Great Bear Initiative, an alliance of nine remote First Nations governments, published guidelines on how community members could build energy-efficient and culturally appropri- ate housing. 6 These guidelines emphasize the importance of housing designs that facilitate traditional customs and lifestyles as well as the importance of resident au- tonomy and engagement to maintain the longevity of housing. Two Manitoba Dene First Nations, Northlands Denesuline First Nation and the Sayisi Dene First Nation, in partnership with researchers from the University of Manitoba, published a toolkit to guide future housing initiatives, inte- grating Dene cultural values into housing design. 7 Through a participatory exchange program, students and community mem- bers co-developed designs and detailed renderings of ten proposed housing units which integrated Dene cultural values through material selection, cultural activ- ities, and food security culminating in the Sekuwe (My House) toolkit. 7 Currently, our team leads the From Harvest to House program, a collabora- tion with multiple First Nations commun- ities throughout Canada to co-develop affordable, safe, healthy and resilient housing. This program consists of com- munity knowledge exchange workshops and co-developed research programs to understand the current state of housing stock by conducting building condition assessments and indoor air quality mon- itoring. We integrate Two-Eyed Seeing, (Etuaptmumk), a guiding principle em- phasizing the integration of Indigenous and Western Knowledge, to foster re- ciprocal learning and ensure Indigenous Knowledge is valued equally alongside academic methodologies. 8 Addressing the on-reserve housing crisis requires continued collaboration, stable long- term investments, and policies that em- power First Nations communities to lead the way in designing and implementing housing solutions tailored to their needs. Collaborative research and engineer- ing are a critical pathway for advancing reconciliation. By working together in equitable and reciprocal ways, these col- laborations can create meaningful and lasting solutions that not only address immediate housing needs but also sup- port long-term community resilience and self-determination. ■ Helen Stopps, Ph.D., P.Eng is an Assistant Professor in Architectural Science at Toronto Metropolitan University (TMU) and co-lead of the From Harvest to House program. Maria Milan is a Ph.D. student in Building Science at To- ron-to Metropolitan University. Odel Linetska is a M.A.Sc stu-dent in Building Science at Toronto Metropolitan Uni- versity. Sarah Haines, Ph.D., is an Assistant Professor in the De partment of Civil & Environmental Engineering at Univer-sity of Toronto and co-lead of the From Harvest to House program. Natalie Clyke is a Project Manager of the From Harvest to House program and Founder and CEO of Rock-Tree Mgo Construction Materials Inc. Becky Big Canoe is the co-founder of the Mno Aki Land Trust, a member of the Keepers of the Circle and the founder of EnviroNative Training Initiatives. REFERENCES: 1.D. Patterson and L. Dyck, “On-reserve housing and infrastructure: recommenda- tions for change,” Standing Senate Committee on Aboriginal Peoples, vol. 4, 2015, pp. 1-67. 2.J. Christensen and P. Andrew, “‘They don’t let us look after each other like we used to’: Reframing Indigenous homeless geographies as home/journeying in the Northwest Territories, Canada,” in Indigenous Homelessness, University of Manitoba Press, Winnipeg, MB, Canada, Oct. 2016, pp. 24-48. 3.Auditor General of Canada, “Federal government failing to improve housing con- ditions for First Nations communities,” Office of the Auditor General of Canada, 2024. https://www.oag-bvg.gc.ca/internet/English/att__e_44454.html. 4.J. S. Lyeo et al., “Ten questions concerning First Nations on-reserve housing in Canada,” Building and Environment, vol. 266, no. 1, 2024. Available: https://doi. org/10.1016/j.buildenv.2024.111544. 5.M. Garneau. The Effects of the Housing Shortage on Indigenous Peoples in Canada: Report of the Standing Committee on Indigenous and Northern Affair. Standing Committee on Indigenous and Northern Affairs (Jun. 2022) 6.D.H. Heerema, “Technical Guideline Development for High Performance Coastal First Nations Housing,” University of British Columbia, 2016. 7.L. Larcombe et al., “Sekuwe (My House): Building health equity through Dene First Nations housing designs,” International Journal of Circumpolar Health, vol. 79, no. 1, 2020. Available: https://doi.org/10.1080/22423982.2020.1717278. 8.A. Marshall and C. Bartlett, “Two-Eyed Seeing for Knowledge Gardening,” En- cyclopedia of Educational Philosophy and Theory, 2018. Available: https://doi. org/10.1007/978-981-287-532-7_638-1. Wintery road leading into a community.Building Science Association of Ontario19 FEATURE By Oskar Linkruus, Nicholas Asistores, and Dr. Taofiq Al-Faesly, Algonquin College’s Algonquin Centre for Construction Excellence Aerogel Insulation in Building Retrofits: Maximizing Efficiency with Minimizing Bulk A erogel, famously known for its use on many of NASA’s missions into the most extreme conditions in the universe, has been used as a light- weight and high-performing insulator for almost 100 years. The material, made by removing the liquid in gels and replacing it with gas, creates a solid that is comprised of 97 per cent air. While this process is expen- sive, technological innovations have made it viable for Aerogel products to be used for residential and commercial construction. PROJECT BACKGROUND While aerogel is more affordable now than ever, it still has a high price tag, lim- iting its economic viability in residential construction. Because of this, this research group will focus on its use in building retro- fits. This scope was chosen specifically, as building retrofits of older homes are gen- erally expensive ventures, to begin with, and are often working with limited space to improve the thermal resistance of the assembly. Two different products, RoVa Shield aerogel coating and Slentite Aerogel pan- els, were tested to determine aerogel’s via- bility as an alternative for building retrofits. RoVa is a South Korean company that produces various aerogel products for construction. The company’s RoVa Shield A wall sample inside the Guarded Hot Box. Photos and graphs courtesy of Oskar Linkruus.Next >