Blower Door Testing
What is a blower door test?
A blower door test uses a specialised, calibrated fan that’s mounted into an external doorway using an adjustable frame and airtight seal.
The fan either pressurises or depressurises the building, and sensors measure how much air flows through the fan to maintain the pressure difference (usually 50 Pascals).
From these readings, we calculate the Air Changes per Hour (ACH50) — a measure of how many times the entire volume of air inside the building is replaced with outside air in one hour at that pressure.
The lower the number, the more airtight the building.
Why that matters: Every uncontrolled air leak increases heating and cooling costs, lets in moisture, and reduces comfort.
Why Airtightness Matter
In Australia’s climate, uncontrolled air leakage can account for up to 25% of a home’s heating and cooling energy use. That’s like leaving a window permanently open.
Airtightness testing can help you:
- Lower energy bills – Less energy lost through gaps and cracks means more efficient heating and cooling.
- Improve comfort – Eliminate cold draughts in winter and hot spots in summer.
- Protect against condensation & mould – Airtightness helps keep moisture under control.
- Enhance indoor air quality – Works best when combined with mechanical ventilation.
- Meet performance targets – Essential for Passive House, NatHERS, or high-performance energy standard
How the test works
Step-by-step process:
Preparation – We close all windows and doors, and temporarily seal vents as needed.
Equipment set-up – A calibrated blower door fan is installed in an exterior doorway.
Pressurisation – The fan pulls air out of the building (or blows it in), creating a pressure difference.
Leak detection – Using smoke pencils, infrared cameras, and hand-held sensors, we identify where air is escaping or entering.
Results – You’ll receive a report showing your home’s airtightness score (ACH – air changes per hour) and recommendations for improvement.
When to Schedule a Blower Door Test
We recommend testing twice during a build for best results:
Mid-Construction Testing
After insulation is installed, before plasterboard or internal wall linings.
This allows any leaks to be easily located and sealed before the building is finished.
Final Testing
At project completion to confirm airtightness results and produce final documentation for certification.
For renovations
Testing before work begins gives you a baseline. A post-renovation test confirms your upgrades improved the building’s performance.
Interpreting the Results
Your airtightness is measured in ACH – Air Changes per Hour at 50 Pascals (Pa) of pressure.
What the numbers mean:
1 ACH or lower – Very airtight (Passive House standard is ≤ 0.6).
3–5 ACH – Reasonably airtight, but improvements possible.
10 ACH or more – Leaky; sealing will significantly improve comfort and efficiency.
We’ll explain your results in plain language, so you know exactly what they mean for your home.
Benefits at a Glance
- Find hidden air leaks early
- Reduce heating & cooling costs
- Increase year-round comfort
- Improve moisture control & prevent mould
- Support compliance with building standards
- Strengthen construction quality control
Benefits of Choosing HiPer Haus
- Certified Passive House Tradesperson – Expertise in ultra-low energy buildings.
- Specialist equipment – Professional-grade testing tools for accurate results.
- Detailed recommendations – We don’t just measure; we help you improve.
- Local experience – Knowledge of South Australia’s climate and building styles.
FAQS
Do I need a blower door test?
If you’re building new, renovating, or want to reduce energy costs, yes — it’s the best way to find hidden leaks.
How long does it take?
Most tests take 2–3 hours, depending on property size.
Will it damage my house?
No. The process is safe for all types of buildings.
What happens if my home ‘fails’?
We’ll show you exactly where the leaks are and how to fix them
Pricing
Every home and building is different, so we provide tailored quotes based on size, construction type, and location.
Contact us today for a personalised quote and find out how affordable improving your airtightness can be.