You could insulate your building with the highest-rated products on the market and still lose a third of your heat. The culprit isn’t bad insulation — it’s thermal bridging, and most building owners have never heard of it.
If you manage a commercial building in Alberta, thermal bridging is almost certainly costing you more than you think. Here’s what it is, how to find it, and what you can do about it.
What is thermal bridging?
A thermal bridge is any spot where a highly conductive material — steel, concrete, aluminum — passes through your insulation layer and creates a shortcut for heat to escape. Think of it like a hole in a winter jacket: even if the rest of the jacket is perfectly insulated, heat pours out through the gap.
In commercial buildings, thermal bridges are everywhere:
- Steel stud framing — Steel conducts heat roughly 1,000 times faster than wood. Cavity insulation rated at R-21 between steel studs delivers an effective R-value of only R-7 to R-9. That’s a 57–65% loss in thermal performance.
- Shelf angles — The structural steel angles that support masonry cladding at each floor cut directly through your exterior insulation, creating a continuous line of heat loss around the building.
- Balcony and canopy connections — A cantilevered concrete balcony slab that passes through the building envelope can account for over 30% of the total heat transfer through your walls.
- Parapet walls — At the roof-wall intersection, thermal bridging through parapets can reduce your wall’s effective R-value by up to 60%.
- Window frames and lintels — Every opening in the envelope introduces additional framing, flashing, and structural support — all of which bridge the insulation.
The R-value on the label isn’t the R-value in your wall
This is the part that surprises most people. The R-value printed on insulation packaging is the nominal R-value — the product’s performance tested alone, under ideal lab conditions. It doesn’t account for studs, fasteners, cladding attachments, or any other real-world penetrations.
The number that actually matters is the effective R-value: the thermal resistance of the entire assembled wall, including all those interruptions.
Here’s how dramatically thermal bridging changes the math:
- A 2×6 wood stud wall with R-24 batt insulation delivers an effective R-value of about R-18 — a 24% loss.
- The same wall framed with steel studs? Effective R-value drops to about R-12 — a 50% loss.
- Steel Z-girts used for cladding attachment are responsible for 36% of total wall heat loss by themselves.
When you add up every thermal bridge in a commercial building — studs, shelf angles, slab edges, parapets, fasteners, window frames — failure to address thermal bridging can account for up to 30% of total building heat loss.
In Edmonton, with over 5,000 heating degree days per year, that 30% translates directly into heating dollars.
It’s not just energy — it’s moisture damage
Thermal bridges create cold spots on interior surfaces. When warm, humid indoor air meets those cold spots, condensation forms. Over time, that moisture leads to mold growth, deterioration of insulation materials, corrosion of structural elements, and poor indoor air quality.
We regularly see buildings where the insulation is in good condition but the wall assembly is underperforming because moisture from thermal bridging has been quietly degrading components for years. The damage is invisible until it’s expensive.
How we find thermal bridges
Thermal bridges are invisible to the naked eye, but they light up under an infrared camera. During a drone-based thermographic inspection, we capture the thermal signature of your entire building envelope — every wall, every roofline, every floor transition.
In winter, thermal bridges appear as warm lines and patches on the exterior surface where heat is bleeding through. The temperature difference between Edmonton’s heated interiors and our winter conditions produces exceptionally clear thermal imagery — the greater the indoor-outdoor differential, the more obvious the defects.
A single aerial thermal survey can identify:
- Every significant thermal bridge in the building envelope
- Missing or displaced insulation
- Moisture intrusion and wet insulation
- Air leakage paths
This moves the conversation from guessing to knowing. Instead of assuming where heat loss is occurring, you have a complete map of it.
From detection to numbers: thermal simulation
Finding a thermal bridge is step one. Quantifying how much energy it’s costing you is step two — and that’s where thermal simulation comes in.
Using 2D and 3D thermal modeling software aligned with ISO 10211 and CSA Z5010 (the Canadian standard now referenced by the National Energy Code), we calculate the actual heat flow through each thermal bridge detail. The output is a set of values — linear thermal transmittance (psi-values) and point thermal transmittance (chi-values) — that quantify exactly how much additional heat loss each bridge is causing.
This matters for two reasons:
- Prioritization. Not all thermal bridges are equal. Simulation tells you which ones are costing the most and where your retrofit dollars will have the biggest impact.
- Code compliance. Alberta adopted Tier 1 of NECB 2020 in May 2024, which requires thermal bridging to be accounted for in energy calculations. The national NECB 2025 goes further, explicitly referencing CSA Z5010 for thermal bridge calculation. When Alberta adopts the next code cycle, thermal bridge modeling won’t be optional — it’ll be a compliance requirement.
What can be done about it
The good news is that thermal bridging is a solved problem. The building science community has developed effective solutions for every common detail:
Continuous exterior insulation is the single most effective strategy. Rigid insulation installed outboard of the framing — unbroken except at service openings — dramatically reduces heat flow through studs and other framing members. This is the reason codes are increasingly requiring continuous insulation in commercial wall assemblies.
Structural thermal breaks — manufactured assemblies placed at balcony connections, shelf angles, and parapet bases — can reduce localized heat loss by up to 90%. These products carry structural loads while interrupting the thermal path.
Thermally improved cladding attachments replace direct steel-to-steel connections through your insulation with fiberglass or thermally broken clips, preserving the continuity of the insulation layer.
Canadian resources in this area are excellent. Morrison Hershfield’s Building Envelope Thermal Bridging Guide catalogues over 600 assembly details with thermal performance data, all searchable online at ThermalEnvelope.ca. When we model your building’s thermal bridges, we can reference these catalogued solutions to recommend specific details that will work for your assembly type.
The business case
Here’s what this looks like in practice. A building owner orders a thermal inspection and discovers significant heat loss at every floor’s shelf angle, at the parapet, and through the steel-framed wall assemblies. Thermal simulation quantifies the losses and identifies the shelf angles and parapet as the highest-impact targets.
The owner applies for Edmonton’s BERA program (up to $75,000 in rebates for envelope improvements), targets the two highest-loss details during a planned re-cladding project, and achieves a measurable reduction in heating costs — with data to prove it.
That’s the approach: inspect, quantify, prioritize, fund, and fix. Every step is grounded in actual measured and modeled data — not estimates, not rules of thumb.
Start with a picture of where you stand
If you don’t know where your building’s thermal bridges are, you’re making energy decisions in the dark. A drone-based thermal inspection gives you a complete picture of your envelope’s actual performance. Thermal simulation turns that picture into numbers you can act on.
Whether you’re planning a retrofit, evaluating a building for purchase, or preparing for Alberta’s next round of energy code adoption, knowing your building’s real thermal performance is the foundation for every smart decision that follows.
Contact us to scope a thermal inspection for your building — and find out what’s really happening inside your walls.