Alberta

Blower Door Testing: What It Is and Why It Matters

Blower door testing is a diagnostic tool used to measure how airtight your building is. A temporary fan is installed in an exterior door to pressurize or depressurize the home, and sensors measure how much air leaks through the building envelope. This helps identify areas of air leakage, confirm construction quality, and ensure energy efficiency compliance.

Blower door testing supports:

  • Better energy performance

  • Improved indoor comfort and air quality

  • Long-term durability

  • Code and rebate program compliance

Who Performs the Test?

We do.

Our certified team conducts professional blower door tests and can help you understand your results, stay compliant, and avoid costly surprises at occupancy.

📄 Download the Blower Door Checklist

Choosing Your Air Leakage Target in Alberta

Under the National Building Code (NBC) as adopted in Alberta:

  • You can model your building at any airtightness level.

  • BUT, if you model your project at less than 2.5 ACH @ 50 Pa, a blower door test is mandatory before occupancy.

What’s the Difference?

  • ACH (Air Changes per Hour) = the number of times indoor air is replaced with outdoor air through leaks each hour at test pressure.

  • A home at 2.5 ACH is tighter, more efficient, and often scores better in energy models.

  • A home at 3.0–3.5 ACH is leakier, but does not require testing — though it may be penalized in energy modelling.

Why It Matters:

If you model at <2.5 ACH and don’t pass a blower door test, you may:

  • Lose compliance with energy modelling or tiered targets

  • Be denied your occupancy permit

  • Be forced to complete costly air-sealing upgrades

Our Advice for Alberta Projects:

Unless you’ve had 3–5 similar homes blower door tested, be cautious about claiming <2.5 ACH without real-world results.

If you’re unsure, it may be safer to:

  • Model at 2.5 ACH to avoid the mandatory test while balancing it with better insulation, windows, or HVAC systems

We’re happy to help evaluate your best path forward — with or without a blower door test.