Building Envelope Leakage Testing (BELT) assesses the airtightness of a building by measuring the amount of air escaping through unintended gaps and openings in the building envelope. Excessive air leakage can compromise energy efficiency, affect internal environmental conditions and impact overall building performance.

HVAC Commissioning undertakes building envelope leakage testing using a blower door system to pressurise or depressurise the building and measure air leakage. Our testing follows the applicable Air Tightness Testing and Measurement Association (ATTMA) technical guidance. With our senior engineer qualified to ATTMA Technical Standard Level 2 (TSL2), we are equipped to test large and complex buildings.

Airtightness testing is also an important part of the Green Star Buildings NZ verification and handover process, helping project teams assess building envelope performance against established targets. Our services can support Green Star projects by providing objective test results and reporting to assist with demonstrating airtightness performance in line with applicable project requirements.

Drawing on our industry training and technical expertise, we establish the required airtightness target based on the building design and applicable project criteria, then assess the completed building against this target. Testing provides measurable results to determine whether the building envelope achieves the required airtightness performance. Where excessive leakage is identified, the results can help inform further investigation and identify areas requiring remedial attention.

By providing independent testing and performance reporting, HVAC Commissioning helps clients verify building envelope airtightness, identify potential deficiencies and support the delivery of energy-efficient, comfortable and well-performing buildings.