Envelope permeability is the term given to building leakage and is measured in cubic meter (m3), per hour (h), per m2 (m2) of building envelope, or m3/h/m2. This measurement is taken at a differential pressure of 50Pa between inside and outside the building. It is tested with a blower door, which is a special type of fan designed to measure building leakage. Depending on how large the building is and permeability requirement, fans can be used in many different configurations.
All buildings leak air and the direct relationship of air infiltration and energy consumption is clear, proven and measurable. Controlling the airtightness of a building enables the mechanical system to maintain the internal conditions with a greater accuracy and better efficiency because it does not have to work against unconditioned air leaking in, or the loss of conditioned air leaking out.
Building efficiency in Australia has not changed significantly since the introduction of Section J in the National Construction Code of Australia. Prior to this there was no real measure of efficiency that buildings had to meet in order to comply. Mandatory building airtightness is the last of the low hanging fruits on improving building efficient without increasing the cost of construction.
The National Construction Code 2019 Section JV4 is the first step on improving building airtightness through measuring the actual buildings, not simulating and assuming the works will be done according to code. It is a direct measurement on the performance of a building envelope and therefore a direct measurement on the quality of construction undertaken because poor quality buildings rarely pass a building leakage test.
Who are Aerotight
Aerotight are dedicated to the design, construction and testing of buildings for airtightness. We take a hands-on approach into educating teams on identifying air leak points before they are built so that the final test is just a formality. The team at Aerotight are experts in working through the practicality, cost and risk of finding the most economical solution that works for your project.
Part of our unique process is to workshop the project team before the start of construction. This enables open discussion and investigation into design elements, management of the build to mitigate risk, as well as prototype testing to ensure the materials and methods used are suitable for the project. This workshop is broken down into 10 steps that can be adopted by any company ranging from small residential to tier 1 commercial construction companies. In addition to this we offer our clients equipment hire so that they can manage small scale testing of their project without the added cost of an airtightness testing company needing to be there.
On average 75% of builders will fail their first air leakage test if the permeability is below 5m3/h/m2 @50Pa
If you have a project with an airtightness test and want to know more, contact the team at Aerotight.
Aerotight are leaders in Air Permeability Performance Testing for Greenstar
Unique to Aerotight, we offer prototype testing for builders to ensure an airtight build
Pre-completion, airleakage detection for large scale data centres
Fire Integrity Room
Non-invasive room testing for project completion and on going maintanace
Compliance testing for cleanrooms is critical to ensure efficient control is main
Aerotight understand how to pass the Defence Building Energy Performance Manual specification
We offer significant discounts to project teams who need training and testing services. The task of knowing where to start and how to finish is often unknown to builders. Aerotight’s engagement throughout the project provides an invaluable resource for both new and experienced builders.
We offer all our client blower door hire options so they can identify leakage points before any full scale testing is conducted.