What a thermal survey shows
An infrared camera reads surface temperature. On a cold day, the interior surfaces of a building print a map of what is behind them.
- Missing or settled insulation shows as cold patches with defined edges.
- Thermal bridging shows as regular lines - studs, joists, girts, steel framing - printing straight through the finish.
- Air leakage shows as irregular plumes fanning out from a gap, usually at the top plate, around windows, at penetrations and at the rim joist.
- Moisture shows as cold areas with soft edges that do not match any framing pattern, because evaporation cools the surface.
Reading which is which is the skill. The camera produces the image; the interpretation is what has value.
Why survey before you spend
At residential scale a survey usually reorders the priority list. The wall someone was about to spend money on turns out to be fine, and the attic hatch, the rim joist and the pot lights turn out to be the actual loss.
At commercial scale the case is stronger still, because the cost of getting the priority wrong is much larger. A survey on a warehouse or an office building routinely changes which surface gets the budget.
Conditions matter
A survey needs a meaningful temperature difference between inside and outside to show anything - which in Alberta means the cold months, and generally not a sunny afternoon when solar gain has loaded the exterior surfaces.
That is a real scheduling constraint. A survey done in mild conditions produces a pretty picture and no information.
What it is not
Thermal imaging does not see through walls, does not measure R-value, and does not by itself confirm moisture - it shows temperature differences that are consistent with moisture and need verification.
Anyone presenting a thermal image as proof of a specific defect without corroboration is overreading the tool. Used properly it is diagnostic; used as a sales prop it is theatre.
Pairing it with a blower door
A thermal survey shows where heat is going. A blower door test measures how much air the building leaks in total.
Run together - camera inside while the building is depressurised - they are far more powerful than either alone, because depressurisation exaggerates the leaks and makes them unmistakable on the image.
Thermal Imaging Insulation Inspection Alberta: Common Questions
Do I need a survey before getting insulation quoted? Not always. On a straightforward job with an obvious problem, no. On a large building, an expensive job, or a problem nobody has been able to explain, it usually pays for itself in better-directed spending.
Will it tell me my R-value? No. It shows temperature differences, not thermal resistance. It tells you where the assembly is failing rather than what it rates.
Can it find a roof leak? It can show anomalies consistent with moisture, which is a strong lead. Confirmation still needs a moisture meter or an inspection.
How long does a survey take? A house is typically a couple of hours in suitable conditions. A commercial building depends on size and access.
Book a survey
Get in touch with the building type and what you are trying to diagnose. See spray foam insulation cost and commercial retrofit.