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From the Ground Up:  ENERQUALITY Project Reveals How Homes Can Achieve Significant Carbon Reductions

Written by ENERQUALITY | Oct 2, 2025 5:38:21 PM

From the Ground Up:  ENERQUALITY Project Reveals How Homes Can Achieve Significant Carbon Reductions

If you walked into this home without knowing its backstory, you might think it was just another new build in a quiet Ontario subdivision. Fresh paint. Open-concept layout. Lots of natural light. Nothing about it screams “high performance” or “experimental.”

But behind the drywall, in the spaces between the studs and beneath the flooring, something remarkable is happening.
This house is estimated to reduce its carbon footprint by 65% over the next 30 years (or 87% reduction in operational carbon year over year) compared to a typical code-built home. It’s doing so without futuristic materials, radical design changes, or sky-high costs, and all the while using less embodied carbon to construct than a conventional home.

The real surprise?

It wasn’t designed as a one-off showpiece. It was built as a proof of concept: a demonstration of how small, carefully chosen upgrades can deliver measurable benefits for the planet and for the community.

The Big Question

The project team, led by ENERQUALITY in partnership with Lakeview Homes, eleven manufacturers and an energy advisor, started with a deceptively simple challenge:

“What if we took a regular home, used materials builders already know, and made it significantly better for the environment, without retraining trades, delaying the build, or blowing the budget?”

The answer would have to meet three conditions:

Be achievable now with readily available products.
Add measurable value for homeowners beyond just lower energy bills.
Offer a repeatable path for other builders to follow without disrupting their business model.

Why This Matters Now

If you’re a homeowner, you’ve probably heard buzzwords like Net Zero, airtightness, and embodied carbon. They can feel abstract, the kind of things you might care about “someday” when you’re replacing your furnace or building your dream home.

But the truth is, decisions made at the construction stage have decades-long consequences. Once a wall is sealed, you can’t easily go back and add insulation. Once ductwork is in, changing it is a costly renovation.

That’s why this project is important: it shows what’s possible when you bake performance into the blueprint from day one, and doing so doesn’t have to mean reinventing the way homes are built.

The Results in Numbers

To understand the impact, let’s start with the data.

A code-built home of this size and layout is estimated to have a 30-year carbon footprint of 133 tonnes CO₂e (including both operational and embodied carbon).

By making targeted upgrades, this home brought that number down to 46.1 tonnes CO₂e, a 65% total reduction.

  • Operational carbon savings: 87%
  • This was driven by a 50% savings in energy usage, thanks to airtightness improvements, exterior insulation, and high-performance mechanical systems.
  • Embodied carbon reduction: 15% over code
  • Achieved by balancing some higher-carbon materials (like spray foam) with other low-carbon substitutions elsewhere.

For the homeowner, those reductions translate into:

  • Lower monthly utility bills
  • More stable indoor temperatures
  • Cleaner, filtered indoor air (even during smog advisories or wildfire smoke)
  • A quieter, more resilient home
  • This wasn’t a “rip-and-replace” strategy. Every choice was deliberate – weighing upfront cost, embodied carbon impact, operational performance, and ease of integration with existing construction practices.
Better Walls Without Overcomplication

The above-grade walls were upgraded from code with 2x6 framing plus R22 spray foam insulation and R5 continuous exterior insulation.

By shifting insulation outward, the home achieved a continuous layer of insulation, eliminating the thermal bridging through the studs, the invisible heat loss, while also supporting moisture control and helping with noise reduction.

The choice of XPS insulation mattered. XPS tends to have higher embodied carbon than other forms of rigid insulation, but here the trade-off was worthwhile: operational savings, moisture performance, familiarity with trades and confidence in the product’s performance outweighed the increase. The lower-carbon formulation was instrumental in further minimizing the increased embodied carbon when compared to others on the market.

Airtightness That Makes a Difference

Measured airtightness came in at 0.4 ACH – far below the 3.0 ACH level typical in code-built homes, and even lower than the 1.5 ACH point where most energy savings start to level off.

Why aim this low if the efficiency gains diminish? Because airtightness not only improves the energy efficiency of the home.

It facilitates:

  • Quieter interiors (fewer drafts, less outside noise)
  • Better air quality (thanks to filtered fresh air via an ERV)
  • Longer “coast times” in extreme weather, where the home maintains a comfortable temperature longer if the power goes out
  • Once airtightness drops below 2.50 ACH, mechanical ventilation is needed to ensure enough fresh air. Instead of an HRV, this home uses a high-efficiency ERV – recovering heat and moisture from outgoing air and delivering fresh, filtered, humidity-controlled air for optimal indoor air quality and comfort.
Windows That Pull Their Weight

Triple-pane windows with a low Solar Heat Gain Coefficient (SHGC) keep summer heat out while minimizing winter heat loss.

The comfort perks are immediate:

  • Reduced outdoor noise infiltration
  • Reduced convection loops that cause the cold-draft sensation when standing near windows in winter
  • Less overheating from the sun in summer
  • And because heating and cooling loads are lower, the home could use smaller, more efficient mechanical equipment — saving both energy and cost.
Smart Trade-Offs in Materials

Some materials, like spray foam insulation, have higher embodied carbon than fibreglass batts. But here, spray foam’s ability to seal complex areas (like rim joists and basement walls) delivered airtightness and comfort benefits that justified its use.

These were balanced with lower-carbon materials elsewhere, such as Lafarge’s reduced-carbon concrete and Brampton Brick products, resulting in a net carbon savings.

The Hiccups (and How They Were Handled)

No project goes perfectly. This one faced a few curveballs:

Foundation curing delay: Lafarge’s lowest embodied concrete mix added two extra days to curing. However, the reductions with this mix were significant enough that with careful scheduling to keep the overall build on track, it was ultimately a good decision.
Mechanical plan revisions: Ductwork Structural constraints required rerouting some ductwork, but proactive collaboration between trades prevented downstream delays.
Solar pivot: Panels were deferred due to high upfront costs. To keep options open, the house was built solar-ready (conduit and truss design means panels can be added later without major retrofits).

These challenges reinforced one of the project’s core messages: performance depends as much on coordination as it does on products.

The Benefits You Can Feel

For homeowners, the technical data translates into lived comfort. The most important outcomes aren’t the ACH numbers or carbon calculations. They’re the everyday experiences:

Walking barefoot on warm basement floors in February
Not having to overuse the AC in August just to feel comfortable
Knowing the air inside is filtered during wildfire smoke or smog advisory days
Enjoying a home so quiet you can hear yourself think.

It’s comfort you notice immediately, and resilience you might not appreciate until you really need it. The goal was a “normal” looking home that quietly outperformed on every front.

However, the reality:

  • Met or exceeded targets for airtightness, carbon reduction, and comfort
  • Early curing delays were absorbed without extending the full schedule
  • Trades did not require retraining, just tighter coordination
  • Fully achievable with materials already in the market

Why This Matters for the Future

If one home can achieve a 65% carbon reduction without disruption, entire subdivisions can. That’s the bigger vision: to show that Net Zero performance – or close to it – can be achieved without increasing the embodied carbon of a home build. It doesn’t need radical re-invention but practical, replicable steps.

As Lakeview Homes’ team put it:

“The jump from ENERGY STAR to Net Zero wasn’t as big as we thought. With the right planning, we’d absolutely do it again.”

For homeowners, that means better homes are within reach today. For builders, it means a pathway to higher performance without higher risk.

The Takeaway

Better design isn’t about chasing the latest gadget or trend. It’s about understanding how each decision, from window glazing to duct layout, affects the whole home over decades of use.

This project proves that when those decisions are made intentionally, we can:

  • Cut carbon in half or more
  • Lower operating costs
  • Improve day-to-day comfort
  • Future-proof homes for changing climates
  • And we can do it now, with the tools we already have.

Want to be part of the next project? Contact Us.