Solar air heating is among the most cost-effective applications of solar thermal energy. These systems are used for space heating and preheating fresh air for ventilation, typically using glazed or unglazed perforated solar collectors. The collectors draw in outside air, heat it using solar energy, and then distribute it through ductwork to meet building heating and fresh air needs. In 2024, Canada led again the world for the at least seventh year in a row in solar air heating adoption. The four key suppliers – Trigo Energies, Conserval Engineering, Matrix Energy, and Aéronergie – reported a combined 26,203 m2 (282,046 ft2) of collector area sold last year. Several of these providers are optimistic about the growing demand. These findings come from the newly released Canadian Solar Thermal Market Survey 2024, commissioned by Natural Resources Canada. Canada is the global leader in solar air heating. The market is driven by a strong network of experienced system suppliers, optimized technologies, and a few small favorable funding programs – especially in the province of Quebec. Architects and developers are increasingly turning to these cost-effective, façade-integrated systems as a practical solution for reducing onsite natural gas consumption. Despite its cold climate, Canada benefits from strong solar potential with solar irradiance in many areas rivaling or even exceeding that of parts of Europe. This makes solar air heating not only viable, but especially valuable in buildings with high fresh air requirements including schools, hospitals, and offices. The projects highlighted in this article showcase the versatility and relevance of solar air heating across a range of building types, from new constructions to retrofits. Figure 1: Preheating air for industrial buildings: 2,750 m2 (29,600 ft2) of Calento SL solar air collectors cover all south-west and south-east facing facades of the FAB3R factory in Trois-Rivières, Quebec. The hourly unitary flow rate is set at 41 m3/m2 or 2.23 cfm/ft2 of collector area, at the lower range because only a limited number of intake fans was close enough to the solar façade to avoid long ventilation ductwork. Photo: Trigo Energies Quebec’s solar air heating boom: the Trigo Energies story Trigo Energies makes almost 90 per cent of its sales in Quebec. “We profit from great subsidies, as solar air systems are supported by several organizations in our province – the electricity utility Hydro Quebec, the gas utility Energir and the Ministry of Natural Resources,” explained Christian Vachon, Vice President Technologies and R&D at Trigo Energies. Trigo Energies currently has nine employees directly involved in planning, engineering and installing solar air heating systems and teams up with several partner contractors to install mostly retrofit projects. “A high degree of engineering is required to fit a solar heating system into an existing factory,” emphasized Vachon. “Knowledge about HVAC engineering is as important as experience with solar thermal and architecture.” One recent Trigo installation is at the FAB3R factory in Trois-Rivières. FAB3R specializes in manufacturing, repairing, and refurbishing large industrial equipment. Its air heating and ventilation system needed urgent renovation because of leakages and discomfort for the workers. “Due to many positive references he had from industries in the area, the owner of FAB3R contacted us,” explained Vachon. “The existence of subsidies helped the client to go for a retrofitting project including solar façade at once instead of fixing the problems one bit at a time.” Approximately 50 per cent of the investment costs for both the solar air heating and the renovation of the indoor ventilation system were covered by grants and subsidies. FAB3R profited from an Energir grant targeted at solar preheating, plus an investment subsidy from the Government of Quebec’s EcoPerformance Programme.   Blue or black, but always efficient: the advanced absorber coating In October 2024, the majority of the new 2,750 m² (29,600 ft2) solar façade at FAB3R began operation (see figure 1). According to Vachon, the system is expected to cover approximately 13 per cent of the factory’s annual heating demand, which is otherwise met by natural gas. Trigo Energies equipped the façade with its high-performance Calento SL collectors, featuring a notable innovation: a selective, low-emissivity coating that withstands outdoor conditions. Introduced by Trigo in 2019 and manufactured by Almeco Group from Italy, this advanced coating is engineered to maximize solar absorption while minimizing heat loss via infrared emission, enhancing the overall efficiency of the system. The high efficiency coating is now standard in Trigo’s air heating systems. According to the manufacturer, the improved collector design shows a 25 to 35 per cent increase in yield over the former generation of solar air collectors with black paint. Testing conducted at Queen’s University confirms this performance advantage. Researchers measured the performance of transpired solar air collectors both with and without a selective coating, mounted side-by-side on a south-facing vertical wall. The results showed that the collectors with the selective coating produced 1.3 to 1.5 times more energy than those without it. In 2024, the monitoring results were jointly published by Queen’s University and Canmat Energy in a paper titled Performance Comparison of a Transpired Air Solar Collector with Low-E Surface Coating. Selective coating, also used on other solar thermal technologies including glazed flat plate or vacuum tube collectors, has a distinctive blue color. Trigo customers can, however, choose between blue and black finishes. “By going from the normal blue selective coating to black selective coating, which Almeco is specially producing for Trigo, we lose about 1 per cent in solar efficiency,” explained Vachon. Figure 2: Building-integrated solar air heating façade with MatrixAir collectors at the firehall building in Mont Saint Hilaire, south of Montreal. The 190 m2 (2,045 ft2) south-facing wall preheats the fresh air, reducing natural gas consumption by 18 per cent compared to the conventional make-up system. Architect: Leclerc Architecture. Photo: Matrix Energy Matrix Energy: collaborating with architects and engineers in new builds The key target customer group of Matrix Energy are public buildings – mainly new construction. “Since the pandemic, schools are more conscious about fresh air, and solar preheating of the incoming fresh air has a positive impact over the entire school year,” noted Brian Wilkinson, President of Matrix Energy. Matrix Energy supplies systems across Canada, working with local partners to source and process the metal sheets used in their MatrixAir collectors. These metal sheets are perforated and then formed into architectural cladding profiles. The company exclusively offers unglazed, single-stage collectors, citing fire safety concerns associated with polymeric covers. “We have strong relationships with many architects and engineers who appreciate the simplicity and cost-effectiveness of transpired solar air heating systems,” said President Brian Wilkinson, describing the company’s sales approach. “Matrix handles system design and supplies the necessary materials, while installation is carried out by specialized cladding and HVAC contractors overseen by on-site architects and engineers,” Wilkinson added. Finding the right flow: the importance of unitary airflow rates One of the key design factors in solar air heating systems is the amount of air that passes through each square meter of the perforated metal absorber,  known as the unitary airflow rate. The principle is straightforward: higher airflow rates deliver more total heat to the building, while lower flow rates result in higher outlet air temperatures. Striking the right balance between air volume and temperature gain is essential for efficient system performance. For unglazed collectors mounted on building façades, typical hourly flow rates should range between 120 and 170 (m3/h/m2), or 6.6 to 9.4 cfm/ft2. However, Wilkinson suggests that an hourly airflow rate of around 130 m³/h/m² (7.2 cfm/ft2) offers the best cost-benefit balance for building owners. If the airflow is lower, the system will deliver higher air temperatures, but it would then need a much larger collector area to achieve the same air volume and optimum performance, he explained. It’s also crucial for the flow rate to overcome external wind pressure. As wind passes over the absorber, air flow through the collector’s perforations is reduced, resulting in heat losses to the environment. This effect becomes even more pronounced in taller buildings, where wind exposure is greater. To ensure the system performs well even in these conditions, higher hourly airflow rates typically between 150 and 170 m³/m² (8.3 to 9.4 cfm/ft2)  are necessary. Figure 3: One of three apartment blocks of the Maple House in Toronto’s Canary District. Around 160 m2 (1,722 ft2) of SolarWall collectors clad the two-storey mechanical penthouse on the roof. The rental flats have been occupied since the beginning of 2024. Collaborators: architects-Alliance, Claude Cormier et Associés, Thornton Tomasetti, RWDI, Cole Engineering, DesignAgency, MVShore, BA Group, EllisDon. Photo: Conserval Engineering Solar air heating systems support LEED-certified building designs Solar air collectors are also well-suited for use in multi-unit residential buildings. A prime example is the Canary District in Toronto (see Figure 3), where single-stage SolarWall collectors from Conserval Engineering have been installed on several MURBs to clad the mechanical penthouses. “These penthouses are an ideal location for our air heating collectors, as they contain the make-up air units that supply corridor ventilation throughout the building,” explained Victoria Hollick, Vice President of Conserval Engineering. “The walls are typically finished with metal façades, which can be seamlessly replaced with a SolarWall system – maintaining the architectural language without disruption.” To date, nine solar air heating systems have been commissioned in the Canary District, covering a total collector area of over 1,000 m² (10,764 ft2). “Our customers have many motivations to integrate SolarWall technology into their new construction or retrofit projects, either carbon reduction, ESG, or green building certification targets,” explained Hollick. The use of solar air collectors in the Canary District was proposed by architects from the Danish firm Cobe. The black-colored SolarWall system preheats incoming air before it is distributed to the building’s corridors and common areas, reducing reliance on natural gas heating and supporting the pursuit of LEED Gold certification. Hollick estimates the amount of gas saved between 10 to 20 per cent of the total heating load for the corridor ventilation of the multi-unit residential buildings. Additional energy-saving strategies include a 50/50 window-to-wall ratio with high-performance glazing, green roofs, high-efficiency mechanical systems, LED lighting, and Energy Star-certified appliances. The ideal orientation for a SolarWall system is due south. However, the systems can be built at any orientation up to 90° east and west, explained Hollick. A SolarWall at 90° would have approximately 60 per cent of the energy production of the same area facing south.Canada’s expertise in solar air heating continues to set a global benchmark, driven by supporting R&D, by innovative technologies, strategic partnerships, and a growing portfolio of high-impact projects. With strong policy support and proven performance, solar air heating is poised to play a key role in the country’s energy-efficient building future. Figure 4: Claude-Bechard Building in Quebec is a showcase project for sustainable architecture with a 72 m2 (775 ft2) Lubi solar air heating wall from Aéronergie. It serves as a regional administrative center. Architectural firm: Goulet et Lebel Architectes. Photo: Art Massif Bärbel Epp is the general manager of the German Agency solrico, whose focus is on solar market research and international communication. The post Op-ed: Canada’s leadership in solar air heating—Innovation and flagship projects appeared first on Canadian Architect.

The International Architecture Exhibition – La Biennale di Venezia,  has returned, with its grand opening held in early May. The exhibition runs until November 23, 2025 The Canada Council for the Arts, Commissioner of Canada’s official participation in the International Architecture Exhibition – La Biennale di Venezia, administers the selection process and oversees the exhibition at the Canada Pavilion. But in addition to the Canada Pavilion, Canadian architects and designers have a presence in several other exhibitions that are part of this year’s festival. Here’s a round-up of the Canadian work in Venice. Picoplanktonics. Photo credit: Valentina Mori Picoplanktonics led by Living Room Collective Canada’s official entry to the Biennale is Picoplanktonics, a 3D-printed living artwork incorporating cyanobacteria—a global first at the intersection of architecture, biotechnology, and art. The exhibition, developed by the Living Room Collective, showcases the potential for collaboration between humans and nature. Picoplanktonics is an exploration of the potential to co-operate with living systems by co-constructing spaces that “remediate the planet rather than exploit it.” The installation transforms the Canada Pavilion into an aquatic micro-ecosystem, where architectural structures grow, evolve, and naturally degrade alongside their living components. It was designed according to regenerative architecture principles, and is not only a built object, but also a breathing organism interacting with its environment, which prompts reflection on potential futures of the built environment. The creative team is led by bio-designer Andrea Shin Ling, alongside core team members Nicholas Hoban, Vincent Hui and Clayton Lee. Etude Ile Verte by Atelier Pierre Thibault. Photo credit Alex Lesage Les boucaneries de l’île Verte by Atelier Pierre Thibault Atelier Pierre Thibault has been invited to participate in this year’s Venice Biennale as the only team from Québec. His project is inspired by the old fish smokehouses, or boucaneries, of Île Verte. With the support of the fifty permanent residents of Île Verte, Atelier Pierre Thibault has designed a participatory architectural project that aims to reinterpret the boucaneries as creative canvases to imagine new uses to strengthen Île Verte’s autonomy. This includes community greenhouses, artist studios, and gathering places. The exhibition aims to highlight, as Thibault puts it, “the strength of a sensitive and collective gesture in response to the erosion of traditional buildings and the major climate challenges faced by inhabitants living year-round in an isolated island environment.” The construction of the installations, along with the exchanges sparked with the community, was documented through photography and video, and captures both the process and the spirit of collaboration that defined the project. Celebrating the Verdoyants’ collective intelligence and inviting reflection on the future of the boucaneries, this participatory project highlights the exemplary and internationally resonant nature of this approach. The Atelier Pierre Thibault project will be on view at the Corderie dell’Arsenale. The pavilion itself will take the form of a temporary, lightweight structure constructed from reused materials, situated on the grounds of the French Pavilion, which is currently undergoing renovation. The curators have selected 50 projects to be featured across six thematic sections: Living With the Existing, the Immediate, the Broken, Vulnerabilities, Nature, and Combined Intelligences. Image courtesy of WZMH Architects Speedstac by WZMH Architects as part of Living With…Combined Intelligences  As part of the exhibition “Living With… Combined Intelligences,” WZMH Architects presents Speedstac, a prefabricated modular precast solution that aims to reimagine how urban areas devastated by war can be rebuilt. Originally designed to accelerate housing construction in Canada, Speedstac took on urgent new relevance following the Russian invasion of Ukraine. With more than 170,000 buildings damaged or destroyed and millions displaced, WZMH’s innovation, developed through its R&D lab, sparkbird, aims to offer a scalable solution: self-contained, plug-and-play building modules with integrated electrical and plumbing systems that can be seamlessly inserted into existing structures. The use of modern materials such as high-performance concrete can reduce the weight of the modules, making them easier to lift and move using conventional crane equipment. Using a robust locking mechanism, several modules can be securely fastened and unfastened as needed, to produce an adaptive modular housing solution. The Speedstac system aims to offer a solution to the challenges of traditional construction methods, enabling faster, more flexible, and more sustainable building projects. The Vivre Avec / Living With exhibition is hosted in the French Pavilion. Presentation, Northern Horizons. Photo credit: Blouin Orzes architectes Northern Horizons by Blouin Orzes architectes as part of Time Space Existence  Through a wide selection of projects—ranging from conceptual works, models and photographs to videos, sculptures and site-specific installations—the exhibition Time Space Existence, hosted by the European Cultural Centre, aims to provoke participants to question their relationship with space and time, re-envisioning new ways of living and rethinking architecture through a larger lens. Quebec firm Blouin Orzes’ participation revolves around their first-hand understanding of Inuit territories, where they have been working since 2000. Their contribution is based on their  recent publication, Northern Journeys. Blouin Orzes’ contribution in on display at the Palazzo Mora, and additional contributions to Time Space Existence are on view at the Palazzo Bembo and Marinaressa Gardens. View of Commercial and Residential Towers from Seymour and West Georgia Streets. Image credit: Henriquez Partners Studio BC Glass Sea Sponge Another contribution to Time Space Existence is the work of Henriquez Partners Studio. The transformative mixed-use development which they are presenting merges architectural innovation, social responsibility and urban revitalization, and has recently been submitted to the City of Vancouver. The project is about ambitious city-building, and aims to unlock public benefits on currently underutilized land in a way that supports some of the city’s most urgent needs, while contributing bold architecture to the city skyline. Four towers, designed by Henriquez, draw inspiration from rare and ancient glass sea sponge reefs, whose ecological strength and resilience have shaped both form and structure. These living marine organisms, which are unique to the Pacific Northwest, aim to serve as a metaphor for regeneration and adaptation. This concept is translated through the architectural language of the towers: silhouettes, sculptural forms, and sustainable performance. The tallest tower, a stand-alone hotel, proposed at 1,033 feet, is shaped by a structural diagrid exoskeleton that allows for column-free interiors while maximizing strength and minimizing material use. Developed in collaboration with Arup, the structural system references the skeletal lattice of sea sponges; a concept researched at Harvard for its groundbreaking structural efficiency. Henriquez Partners’  contribution is on display at Palazzo Bembo. Renewal Development Shishalh Project Duplex Renderings – Image credit: Renewal Development Shíshálh Nation: Ten Home Rescue Project as part of theLiving With / Vivre avec exhibition Vancouver-based company Renewal Development has been selected to appear as part of the French Pavilion’s exhibition on housing innovation. In 2024, Renewal Development partnered with developer Wesgroup and the shíshálh Nation to relocate ten high value Port Moody homes set for demolition to the shíshálh Nation on the Sunshine Coast. The Nation has been experiencing an acute housing shortage with 900 Nation members currently on a waitlist for housing. Renewal Development says that this initiative reflects its “deeply held values of sustainability, and reconciliation” and its “work to offer real-world solutions to waste and housing shortages by reimagining what already exists.” The project will be on display in the French Pavilion. The following is a list of other Canadian groups and individuals contributing to this year’s Venice Biennale: On Storage Brendan Cormier is a Canadian writer, curator, and urban designer based in London. He is currently the lead curator of 20th and 21st Century Design for the Shekou Partnership at the Victoria and Albert Museum. Prior to this he served as the managing editor of Volume Magazine. La Biennale di Venezia and the Victoria and Albert Museum, London present for the ninth consecutive year the Applied Arts Pavilion Special Project titled On Storage, curated by Brendan Cormier, in collaboration with Diller, Scofidio + Renfro (DS+R). It explores the global architecture of storage in service of the circulation of things, and features a newly commissioned six-channel film directed by DS+R. From Liquid to Stone: A Reconfigurable Concrete Tectonic Against Obsolescence Inge Donovan, based in Boston, achieved her Bachelor of Arts in Architectural Design and Architectural History, Theory and Criticism from the Daniels Faculty of Architecture at the University of Toronto in 2019 after growing up in Nova Scotia, Canada. The Curse of Dimensionality Adeline Chum is currently a Graduate Research Assistant at the Center for Spatial Research and third-year student in the MArch Program at GSAPP. She has received her Bachelor of Architectural Studies from the University of Waterloo, Canada and has worked in small and medium-sized architecture firms in Toronto, New York, and London. Oceanic Refractions Elise Misao Hunchuck, born in Toronto and currently based Berlin and Milan, is a transdisciplinary researcher, editor, writer, and educator. Her practice brings together architecture, landscape architecture, and media studies to research sites in Canada, Japan, China, and Ukraine, employing text, images, and cartographies to document, explore, and archive the co-constitutive relationships between plants, animals, and minerals—in all of their forms. SpaceSuits.Us: A Case for Ultra Thin Adjustments Charles Kim is a designer currently based in Boston. Stemming from his background in architecture, he is interested in materials, DIY, and the aesthetics of affordability. Since graduating from Harvard Graduate School of Design in 2022, he has been working as an architectural designer at Utile. Uncommon Knowledge: Plants as Sensors Sonia Sobrino Ralston is a designer, researcher, and educator, and is currently an Assistant Teaching Professor in Landscape Architecture and Art + Design at Northeastern University in the College of Arts, Media, and Design. She is interested in the intersections between landscape, architecture, and the history of technology. Doxiadis’ Informational Modernism Mark Wasiuta is Senior Lecturer in Architecture at Columbia GSAPP and Co-Director of the Critical, Curatorial and Conceptual Practices in Architecture program. Wasiuta is recipient of recent grants from the Onassis Foundation, the Asian Cultural Council, NYSCA, and the Graham Foundation, where he was an inaugural Graham Foundation Fellow. Blue Garden: The Architecture of Emergence Tanvi Khurmi, based in London, UK, is a multidisciplinary designer and artist. Her practice is focused on addressing and combatting issues surrounding the climate crisis. After receiving a Bachelor’s in Architecture with a minor in Environmental Studies from the John H. Daniels Faculty of Architecture at the University of Toronto, she earned a Masters of Architecture in Bio-Integrated Design at the Bartlett School of Architecture at University College London. Design as an Astronaut Dr. Cody Paige is the Director of the Space Exploration Initiative at the MIT Media Lab, a team of 50+ students, faculty, and staff building and flying advanced technology for space exploration. The Initiative focuses on helping students take their research into space. The pipeline developed to achieve this works with students from across the Media Lab and the MIT community to prototype space-related research in the lab, fly and test them in microgravity on parabolic and suborbital flights, and finally to take them to the International Space Station or on to the Moon. Cody also has a background in geology, specifically quaternary geochronology, and completed her Master of Applied Science at the University of Toronto in Aerospace Engineering and her Bachelor of Applied Science from Queen’s University in Engineering Physics.   The post Round-up: Canadian-led exhibitions at the 2025 Venice Biennale appeared first on Canadian Architect.