Canada's Building Codes Are Getting Stricter — Here's What That Means for Your Windows

Between 2020 and 2030, every major Canadian building code — federal, provincial, and municipal — is tightening thermal performance requirements for windows. The direction is not ambiguous: glazing that was adequate for code compliance in 2015 will be legally insufficient in new construction by the end of this decade. Fabricators who understand this trajectory now can position for it. Those who discover it at tender time will be scrambling.

The National Model Code trajectory

Canada's National Building Code (NBC) is not mandatory directly — it serves as a model that provinces adopt, adapt, and enforce through their own codes. But it sets the direction. The 2020 edition introduced a tiered energy performance framework, replacing the single prescriptive path with five increasingly demanding performance tiers. Tier 1 represents code minimum; Tier 5 represents near-net-zero energy-ready performance.

The 2025 National Model Codes update takes this further: for the first time, the National Energy Code for Buildings (NECB 2025) introduces explicit greenhouse gas emission intensity limits, not just energy use limits. This is a structural shift. A building can reduce energy consumption through efficiency while still running on a high-emissions fuel source — the 2025 codes address that gap directly.

Ontario: Step Code and SB-12

Ontario has been the most aggressive Canadian province in pushing residential energy performance. The Ontario Building Code's Supplementary Standard SB-12 provides the energy efficiency requirements for houses and small buildings. The "Step Code" structure — five tiers, with Step 5 being the highest — has been rolling out since 2017, with municipalities increasingly requiring higher steps for new residential construction.

For windows specifically, Step Code compliance in Ontario is assessed through the whole-building energy model, not just the glazing specification in isolation. However, the window U-value has an outsized influence on overall building energy performance — particularly in Ontario's Climate Zones 5 and 6 (Toronto area and northern Ontario respectively), where heating degree days are significant.

Passive House and Step 5 project teams targeting the highest tier of compliance consistently find that whole-window U-values below 0.45 W/m²K are required to meet the energy model targets without overbuilding the wall insulation or mechanical systems. The centre-of-glass U=0.40 W/m²K of VIG Horizon's 4TL+V+4T configuration provides the performance headroom those models require.

Quebec: Code de construction and Régie du bâtiment

Quebec's building code — the Code de construction du Québec (CCQ) — adopts NBC provisions with Quebec-specific modifications. The Régie du bâtiment du Québec (RBQ) administers enforcement. Quebec's climate context is demanding: the province spans Climate Zones 6 through 8, with Montreal at Zone 6 and northern Quebec at Zone 8. Heating degree days in Quebec City exceed those in Toronto by approximately 30%.

Quebec has also been progressively tightening its energy performance requirements through the Novoclimat 2.0 program — a voluntary residential energy standard that is increasingly referenced in social housing procurement and becoming a de facto market requirement for premium residential construction. Novoclimat 2.0 window requirements align closely with Passive House targets, making high-performance glazing a central specification concern.

British Columbia: the Energy Step Code

BC's Energy Step Code (BCESC) has been the most thoroughly implemented provincial performance standard in Canada. As of 2023, municipalities across BC have adopted Steps 2 through 4 as minimums for new construction. The province's trajectory is toward Step 5 (net-zero energy ready) as the baseline requirement for market housing by the late 2020s.

BC's climate diversity — from Zone 4 (Vancouver Island) to Zone 7 (Prince George and northern BC) — means window U-value requirements vary significantly across the province. But in Zones 6 and 7, which cover most of BC's interior, high-performance glazing is not a premium option; it's a code necessity.

Federal: the Net-Zero Emissions Buildings Strategy

Canada's 2030 Emissions Reduction Plan includes a commitment to require that all new buildings built from 2030 onward be net-zero-ready. The Canada Green Building Council's Zero Carbon Building Standard is already being applied to federal government construction procurement. Institutional construction — hospitals, schools, federal offices — is increasingly procured under these standards, creating a growing segment of commercial projects where high-performance glazing is not a specification choice but a contractual requirement.

What this means for fabricators specifying for 2026 and beyond

The window fabricator who can offer a certified glazing option that clears the U=0.40–0.45 threshold — with documentation — will win projects that competitors cannot bid on equally. SGCC certification, TÜV Rheinland thermal data, and CAN/CGSB 12.1-2022 compliance documentation are the paper trail that energy modellers, permit officers, and institutional procurement officers require.

Fabricators adding VIG to their product line today are not early adopters chasing a niche. They are positioning for code requirements that will be mandatory within 3–5 years across most Canadian jurisdictions.