Éco-bâtiment turned to ACAL System, a volumetric modular builder based in Québec that specializes in aluminium-framed units. ACAL units take advantage of aluminum’s lightweight, structural integrity and superior longevity, and combine it with a high-efficiency, LEED/Novoclimat pre-certified thermal envelope.
ACAL has completed over 200 LEED-certified projects across Canada. Its website currently shows a wide variety of tiny homes, duplex, triplex, quadruplex and eight-plex designs, each offering optional levels of completion.
The collaboration between Construction Éco-bâtiment and ACAL resulted in what Miguel Vaillancourt, president of Construction Éco-bâtiment, called “a world-first”, a six-unit, three-storey residential complex named Lofts de l’Aluminium.
The modules were built with such exact precision that the units were assembled onsite in just one day. While the efficiency of the assembly is impressive, equally important were the operational cost benefits made possible by choosing aluminum construction.
High levels of closed-cell insulation (EPS) were incorporated into the units; R42 in the walls, R50 in the floors and R70 in the roof. Together with triple-glazed windows, this has reduced heating and cooling costs for tenants by an estimated 50 per cent. Insurance costs are also reduced due to the higher fire protection offered by the aluminium. Over the longer term, the combination of aluminum and EPS means the structure will not rot, rust, decompose, or promote mold growth, resulting in a healthier indoor air quality for tenants.
From an embodied carbon perspective, the aluminum is produced in Québec using hydroelectricity, arguably the greenest power source in the world. Being lighter than typical wood-cellulose units, the aluminum/EPS volumetric units reduced foundation requirements and associated costs by about 30%.
Vaillancourt estimates the overall completion time for the Lofts de l’Aluminium project was 60 per cent less than traditional building methods, including onsite detailing such as drywall joint finishing and painting and floor covering installation. However, ACAL has since improved its factory processes so that fully complete interiors can be delivered onsite in the future.
Lofts de l’Aluminium’s final cost was about $2.3 million, more than half of which came from the Québec Affordable Housing Program and AluQuébec. The project also won Écotech Québec’s 2024 “Eureka! Prize” in the Real Estate category.
