A new report from the Residential Construction Council of Ontario (RESCON) puts a hard dollar figure on the escalating tariff fight: counter-tariffs imposed Sept. 8 will add $9,000 to $14,000 to the cost of a typical Ontario single-detached home and $18,000 to $28,000 to a mid-rise unit, according to a RESCON report. Those increases land on top of the $15,000 to $25,000 load homes were already carrying from measures imposed in March 2025.
The report, prepared recently by RESCON, arrives as Canada and the U.S. exchange tit-for-tat measures that are reshaping cost assumptions for homebuilders on both sides of the border. The new counter-tariffs go beyond the headline totals: the release lists cost increases for structural steel and rebar, wiring and vinyl products, radiators and cabinet hardware, carpets and heat pumps. The report arrives after months of back-and-forth trade measures between the two countries. The March 2025 measures had already loaded $15,000 to $25,000 onto homes; the Sept. 8 counter-tariffs layer additional cost on top, compounding the affordability challenge for new construction.
Materials hit by counter-tariffs
The report lists a range of inputs facing increases:
- Structural steel and rebar
- Wiring
- Vinyl products
- Radiators and cabinet hardware
- Carpets
- Heat pumps
For fenestration, the vinyl category is the most direct signal, but the broader list shows that tariff exposure cuts across the entire residential building envelope.
For residential builders and fenestration suppliers, the numbers signal that window and door packages will face renewed cost pressure. The inclusion of vinyl products in the tariff-affected list matters directly for the glazing industry, the release notes. Vinyl is a common feedstock for window frames and door components in Canadian low-rise construction, so any tariff-driven bump in that category flows into fenestration line items. Builders and specifiers who have locked in package pricing for upcoming phases may face change orders or renegotiations as material costs move. Window and door packages are typically specified early in a project's design, often before framing starts. When material tariffs change mid-cycle, builders cannot always revisit those specs without delay. The report's tariff list means fenestration suppliers may need to reprice future projects or negotiate with builders on how to share the cost increase. In multi-residential work, where mid-rise units face an $18,000 to $28,000 tariff hit, the impact on building envelope budgets is magnified across dozens or hundreds of suites.
That cost pressure is landing squarely on the building envelope. In Canadian residential construction, vinyl is widely used for window frames, patio doors and exterior door components. While the RESCON report does not break out the fenestration share of the $9,000 to $14,000 increase for a single-detached home, the inclusion of vinyl products in the tariff-affected list means window and door budgets are directly exposed. Fenestration suppliers also operate within performance frameworks such as ENERGY STAR Canada and CSA A440. Tariff-driven input costs do not change those requirements, but they make it more difficult for builders to hold specifications without passing higher costs down the supply chain. The report does not quantify how much of the total tariff burden will fall on fenestration compared with other trades, but the vinyl reference signals that windows and doors are part of the exposure.
Ontario GDP and construction jobs under pressure
The macroeconomic drag extends beyond individual home costs. The release states modelling by the Association of Municipalities of Ontario and Oxford Economics put the Ontario hit at $2.68 billion of GDP and 14,000 construction jobs in 2026 — before the Sept. 8 counter-tariffs were implemented. A preliminary read suggests 2027 housing starts in Ontario could run 8,000 to 12,000 units below the current CMHC baseline if no residential remission is granted. The preliminary 2027 housing starts read is contingent on no residential remission being granted, leaving open the possibility that policy action could cushion the blow.
Those figures translate into fewer projects for glazing contractors, window fabricators and door suppliers who depend on housing starts. A slowdown of that scale would ripple through the building envelope supply chain as builders re-scope packages or defer multi-residential work. The report does not specify a separate job-loss figure for fenestration, but the construction-wide impact indicates that trades supporting new housing will feel the contraction. For a sector already navigating material pricing volatility, the tariff-driven escalation adds another layer of planning risk on both sides of the border. For glazing contractors, the connection between housing starts and fenestration demand is direct: fewer starts mean fewer window and door packages. The report's 8,000 to 12,000 unit deficit below the CMHC baseline, if it materializes, would remove a substantial chunk of Ontario fenestration work from the 2027 pipeline. Suppliers that have invested in capacity for a projected housing ramp-up would face underutilization. The report does not break out fenestration-specific employment, but the 14,000 construction job loss figure implies cuts across all envelope trades.
Builders warn costs will pass to buyers and renters
RESCON president Richard Lyall said in a statement that the counter-tariff response was necessary even though it hurts homebuilding. “This should not, in any way, be construed as a criticism of the Canadian government’s decision to respond to the U.S. with counter-tariffs,” Lyall said. “Faced with substantial U.S. tariffs, Canada had little choice but to act, as no sovereign nation can simply stand aside while key industries are targeted with punitive trade measures.”
He added that the measures are not prosperity measures and will make building homes more expensive in both Canada and the U.S. “Both Canada and the U.S. find themselves struggling with severe housing affordability challenges, the last thing we need is an escalating tariff war that drives up the cost of building homes,” Lyall said. “Yet that is precisely where we find ourselves today. The trade war between the two closest economic partners in the world will only make the housing crisis worse.”
Lyall also pointed to a report done by Oxford Economics for the Canadian American Business Council showing that a complete breakdown of the U.S.-Mexico-Canada Agreement could result in cumulative economic losses reaching U.S. $1.4 trillion in the U.S. and Cdn. $523 billion in Canada. By contrast, an improved agreement could add U.S. $432 billion to American GDP and Cdn. $253 billion to Canadian GDP over the next decade while supporting tens of thousands of additional jobs.
“Imposing tariffs has created a problem where none existed,” Lyall said. “It’s akin to shooting yourself in the foot. Tariffs are not the answer. And they only add to our housing supply and affordability crisis. You don’t build more homes by imposing tariffs and hiking prices.”
Lyall's warning that builders cannot absorb the increases without passing them on to homebuyers and renters applies directly to fenestration. When window and door budgets rise, builders may substitute lower-cost glazing systems or defer upgrades to keep overall home prices within reach. That shifts demand across the fenestration market, benefiting some product categories while squeezing others. The report does not predict specific substitution patterns, but the direction of cost pressure is clear.
For the glazing industry, the RESCON report underscores a broader point: trade policy is now a material cost driver for windows, doors and the entire building envelope. The $9,000 to $14,000 single-detached tariff bite may not appear as a separate fenestration line, but it will be felt in every vinyl window frame, every patio door and every exterior door component specified on Ontario jobsites. As the tariff standoff continues, builders and suppliers will be watching closely for any residential remission or policy shift.