Blower Door Pressure Testing
With my RetroTec devices installed I have a controllable barrier across the building envelope. This allows me to induce and measure pressure differentials and airflow, which facilitates the calculation of building leakage. It also allows me to use thermographic imaging to visually identify specific areas of leakage.
Blower door testing is a diagnostic procedure we as Energy Advisors use to measure the air tightness of buildings. It involves using a powerful fan (the blower door) mounted into the frame of an exterior door. The process helps identify air leakage in the building envelope, which is crucial for several reasons:
Process of Blower Door Testing:
Setup: A blower door unit, consisting of a calibrated fan, a door panel system, and pressure gauges, is installed in an exterior doorway of the building.
Creating a Pressure Difference: The fan is used to either depressurize or pressurize the building by blowing air out of or into the building, creating a pressure difference between the inside and outside. This simulates the effects of wind pressure or the stack effect on the building.
Measuring Air Leakage: The pressure difference forces air through all unsealed cracks and openings in the building envelope. The rate at which air must be added or removed to maintain a certain pressure difference indicates the building's air tightness.
Detection of Leaks: While the building is pressurized or depressurized, the auditor may use smoke pencils, infrared cameras, or other methods to visually locate the points of air leakage.
Importance of Blower Door Testing:
Energy Efficiency: Identifying and sealing leaks improves the thermal envelope of a building, reducing the need for heating and cooling, thus lowering energy consumption and costs.
Indoor Air Quality: By controlling air leakage, blower door testing helps in managing ventilation and reducing the infiltration of pollutants, moisture, and allergens into the building, enhancing indoor air quality.
Comfort: Reducing drafts and cold spots by sealing leaks improves the comfort levels within the building for occupants.
Building Durability: Moisture control through improved air tightness helps prevent structural damage caused by moisture accumulation, thereby extending the building's lifespan.
Compliance and Performance Verification: Many building codes and green building certifications require a certain level of air tightness, which can be verified through blower door testing. It ensures that the building meets specified performance standards.
In Passive House we are looking for 0.6 at ACH50, passive house EnerPhit 1.0, for different levels of BC Energy Step Code we have different air tightness targets to meet.