Blower Door Testing
FOr Southern Highlands
Measure how airtight your building really is
Blower door testing measures uncontrolled air leakage through the building envelope using a calibrated fan and specialised pressure testing equipment. During the test, the fan creates a controlled pressure difference between the inside and outside of the building, allowing us to measure how much air is moving through gaps, cracks and other leakage points.
This provides a clear indication of how airtight the building is performing. It can also help identify areas where outside air is entering the home or conditioned air is escaping, such as around windows, doors, service penetrations, ceiling junctions and other parts of the building envelope.
Uncontrolled air leakage can contribute to drafts, uneven indoor temperatures, increased heating and cooling demand, and reduced overall comfort. By identifying these leakage areas, blower door testing gives homeowners, builders and designers useful information that can support better sealing, improved energy efficiency and stronger overall building performance.
The test is suitable for new homes, renovations, existing homes and high-performance building projects where a more accurate understanding of airtightness is required.
WHY BLOWER DOOR TESTING MATTERS?
A blower door test gives you a clear picture of how well the building envelope is sealed. It helps identify unwanted air leakage that can affect comfort, energy use and overall building performance.
Improve Comfort
Uncontrolled air leakage can create cold drafts, hot spots and uneven temperatures throughout the building. Blower door testing helps identify where outside air is entering or conditioned air is escaping, making it easier to improve indoor comfort.
Improve Energy Efficiency
Air leakage can increase the amount of heating and cooling required to maintain a comfortable indoor temperature. Finding and reducing unnecessary leakage can help improve the overall energy performance of the building.
Verify Building Performance
A blower door test provides a measurable airtightness result rather than relying only on visual inspection. This helps builders, designers and homeowners better understand how effectively the building envelope is performing.
Identify Leakage Areas
The pressure created during testing can help locate areas of unwanted air leakage around windows, doors, service penetrations, ceiling junctions and other parts of the building envelope.
How a Blower Door Test Works
A blower door test uses a calibrated fan temporarily installed in an external doorway to create a controlled pressure difference between the inside and outside of the building. This allows us to measure how much air is leaking through the building envelope.
1. Prepare the Building
Windows and external doors are closed and the building is prepared so the test can be carried out under controlled conditions.
2. Install the Blower Door
A temporary frame, airtight panel and calibrated fan are installed in an external doorway.
3. Create a Pressure Difference
The fan is used to pressurise or depressurise the building, creating a controlled pressure difference between indoors and outdoors.
4. Measure Air Leakage
The testing equipment measures the airflow required to maintain the pressure difference. This gives us a measurable indication of the building’s airtightness.
5. Identify Leakage Areas
While the building is under pressure, significant air leakage areas can be investigated around doors, windows, penetrations, ceiling junctions and other parts of the building envelope.
6. Review the Results
The test results are reviewed so the building’s airtightness performance can be understood and areas requiring further attention can be identified.
From setup to results, the process provides a practical and measurable way to understand how well the building envelope is performing.
Who Is Blower Door Testing For?
Blower door testing is useful for anyone wanting to understand or improve the airtightness and energy performance of a building.
New Homes
Verify the performance of the building envelope before handover and identify areas of unwanted air leakage.
Renovations
Compare building performance before and after improvements and confirm whether sealing work has been effective.
Existing Homes
Investigate drafts, comfort problems, uneven temperatures and areas where conditioned air may be escaping.
High-Performance Homes
Support projects focused on improved energy efficiency, airtight construction and better indoor comfort.
Builders & Architects
Provide measurable information about the building envelope and help identify areas that may require further attention.
Homeowners
Understand how airtight your home is and where improvements may help reduce uncontrolled air leakage.
Blower door testing can be used as part of new construction, renovation, troubleshooting or general building-performance assessment.
What You Receive After Testing
After the blower door test is completed, HGX provides clear information about the building’s airtightness performance and the areas that may need further attention.
Airtightness Result
A measured result showing the building’s overall air leakage performance under the test conditions.
Test Information
Key details from the test, including the building tested, the test conditions and the measured pressure used during testing.
Leakage Observations
Notes on significant areas of unwanted air leakage identified during the test where practical.
Problem Areas
Identification of locations that may require further sealing or investigation, such as doors, windows, penetrations, ceiling junctions or other parts of the building envelope.
Practical Recommendations
Where appropriate, HGX can provide general recommendations on areas that may benefit from further sealing, inspection or building-envelope improvement.
The aim is to give you a clear, measurable understanding of how the building is performing and where improvements may have the greatest impact.
READY TO TEST YOUR BUILDING?
Book a Blower Door Test
Whether you are building a new home, renovating, investigating drafts or checking overall building performance, HGX can help you understand how airtight your building really is.
Our blower door testing service provides a measurable airtightness result and helps identify areas of unwanted air leakage that may be affecting comfort and energy performance.