In a province where construction cranes rarely pause, the 2025 Ontario Embodied Carbon Awards gathered practitioners to show that material emissions were not an abstract accounting exercise but a design constraint shaping decisions from the quarry to the jobsite and back again through end-of-life. Held at The Great Hall in Toronto by the Toronto and Ottawa hubs of the Carbon Leadership Forum, the third annual ceremony trained attention on the 11 percent of global emissions tied to materials and the outsized share embodied carbon carries in new construction. With operational energy rapidly decarbonizing through electrification and cleaner grids, teams across Ontario pivoted toward the harder question: how to build less carbon into the bones of buildings while keeping performance, cost, and constructability in balance.
What The Awards Reveal Right Now
This year’s cohort underscored how low-carbon materials have matured from pilot to playbook. Mass timber appeared as structure and hybrid framing, low-carbon concrete moved from a few podium pours to whole-building strategies, and bio-based assemblies—straw, cellulose, and plant-derived finishes—took the stage as carbon stores rather than mere insulators. The common thread was a whole-life mindset: combine low-embodied-carbon shells with electrification and onsite renewables to drive down both up-front and operating emissions. Moreover, teams leaned on life-cycle assessment at design and post-construction phases, using audits to reconcile models with actual mixes, volumes, and waste.
Equally telling was what did not rely on novelty. Retrofit and reuse set the baseline for reductions, conserving structural frames and deferring high-emission replacements. Municipal standards and city-led benchmarking translated research into requirements, raising the floor across portfolios instead of championing one-off exemplars. Collaboration cut across roles: suppliers disclosed mix data, developers shared as-built results, and municipalities compared sites to calibrate targets. The tone was pragmatic rather than speculative, and the results pointed to a sector that treated embodied carbon as solvable now, not someday, with clear methods and measurable outcomes.
Big Buildings, Small Footprints
Ontario’s larger civic work proved that scale did not have to inflate carbon intensity. The Peel Police Operational Support Facility in Mississauga, a 200,000-square-foot, fully electric complex, wove mass timber with low-carbon concrete in foundations and cores while coupling structure with an onsite solar array. The design targeted an embodied carbon intensity of 276 kgCO2e per square meter, a number rooted in robust modeling rather than aspiration. Backing it was policy: the Region of Peel is delivering 10 facilities under a net-zero standard, sharpening guidance by mandating building LCAs that quantify the consequences of every material choice.
That alignment between standards, structure, and systems mattered beyond a single project. Mass timber reduced high-impact steel and concrete in superstructures, while optimized low-carbon concrete mixes transferred early gains into slabs and cores without tripping schedule or strength. Electrification then closed the loop by locking in clean operations as grids continue to improve. This pairing turned risk into process: suppliers committed to consistent mixes, contractors tracked pour data, and design teams calibrated trade-offs with transparent baselines. The lesson was not about hero materials alone but about orchestrating choices that let policies, procurement, and detailing reinforce each other.
Small-Scale, Bio-Based Breakthroughs
At the opposite end of the spectrum, the Douro Farmhouse showed how plant-based assemblies could deliver ultralow embodied carbon with health and resilience benefits baked in. The 4,000-square-foot home rested on minimal concrete posts, with straw bale walls that stored 9,588 kilograms of CO2 and cellulose insulation that held another 2,642 kilograms. The resulting embodied carbon intensity of roughly 28 kgCO2e per square meter placed the project in rare company for a new build. Local sourcing reduced transport impacts, while earth finishes and non-toxic materials prioritized indoor air quality alongside carbon accounting.
The farmhouse also illustrated a subtle shift in framing: sequestration was not a marketing line; it was a structural strategy. Bio-based layers served as enclosure, fire-safe insulation, and a carbon vault, all while remaining compatible with conventional trades. Detailing balanced moisture management with airtightness, ensuring durability without petrochemical dependence. Because the envelope carried so much of the carbon story, design decisions emphasized continuous layers and simple transitions that minimized waste on-site. The outcome hinted at broader applicability, from rural homes to infill housing, where modular straw or cellulose systems could scale without exotic supply chains.
Retrofits, Audits, And The Wider Map
Transforming existing stock remained the fastest route to embodied savings, and 50 Torbolton Drive in Rexdale showed how disciplined detailing could rescue value from a flood-prone shell. Once vacant, the two-story structure became 17 three-bedroom townhomes after full replacement of finishes, major envelope upgrades, and complete mechanical and electrical swaps. The team specified mineral wool for continuous insulation to trim embodied emissions while controlling cost and improving durability. The philosophy was straightforward: do the simple things well, from clean thermal lines to right-sized systems, instead of chasing headline-grabbing inventions that complicate delivery.
Transparency took a leap on the new-build side as well. Daniels on Parliament advanced beyond typical LCA boundaries with Ontario’s largest deployment of Holcim’s ECOPact, exceeding 22,000 cubic meters and constituting 73 percent of the project’s concrete by volume. Crucially, the team ran a public design-versus-as-built embodied carbon audit, tracking pour volumes, strengths, additives, and waste to reconcile predicted and actual impacts. That process turned measurement into management, revealing where mix optimizations held in the field and where sequencing or tolerances nudged results. The audit set a precedent: carbon claims traveled with documentation, not assumptions.
Landscapes, Policy, And Public Space
Embodied carbon did not stop at the building’s edge, and Toronto’s Landscape Carbon Benchmarking Study with DTAH provided a first-of-its-kind Canadian reference for the public realm. By analyzing 10 development sites, the team quantified the emissions and sequestration tied to planting, soil, hardscape, and site furniture, then explored redesigns that pulled clear levers. One scenario reduced embodied carbon by 34 percent while increasing sequestration by 325 percent by trading hard surfaces for living systems. The study translated those findings into a practical toolkit, informing municipal standards that guided designers toward lower-carbon site packages without compromising function.
The shift was more than a new checklist; it corrected a blind spot in traditional LCAs that often undercounted site work. Designers gained a way to compare paving choices, soil blends, and planting densities with embodied impacts in view, while municipal reviewers received benchmarks that made compliance predictable. In turn, contractors could plan phasing and procurement around lighter materials and improved soil carbon outcomes. When paired with building-level strategies, these landscape moves broadened the reduction map, opening fresh opportunities for sequestration that worked with urban form, stormwater goals, and heat-mitigation strategies already on civic agendas.
Standards, Culture, And The Next Moves
Scaling depended on governance and practice moving together, and Ontario’s examples showed how that alignment took shape. Peel Region’s net-zero standard pushed lessons from one facility across a program, de-risking material substitutions through repeatable details and supplier partnerships. Toronto’s benchmarking converted research into guidance, allowing development teams to set targets early and adjust designs before carbon costs hardened. Meanwhile, BDP Quadrangle Studio demonstrated that firm-wide discipline could deliver at scale: a Science Based Targets initiative–validated 46.2 percent emissions-reduction target, surpassed last year, and more than 100 life-cycle assessments covering over 3 million square meters established a culture where data steered decisions.
The path forward was already visible in these moves and called for tangible steps that project teams could deploy. Specifications had favored low-carbon concrete families with documented mix performance; hybrid timber-concrete systems had balanced structural demands and carbon; bio-based insulation and assemblies had carried dual roles as enclosure and storage; and LCAs had shifted from optional to standard, including as-built audits. Portfolios had set carbon caps by typology, and public realm projects had adopted landscape benchmarks. Taken together, these practices turned embodied carbon from a problem statement into a coordinated workflow that teams could scale across budgets, sites, and schedules.
