Air Permeability Performance Testing
The unintentional air lost through a buildings envelope has been recognised as one of the leading causes of sub-level performance of energy efficient buildings in all climate zones. Air sealing and pressure testing is common in Europe and North America, because it is recognised that a well sealed building is much more comfortable and safe for its occupants and more energy efficient in operation.
Existing and new buildings in Australia are considered very leaky when benchmarked against international counterparts. To help counter this poor performance, the Green Building Council of Australia has introduced in its Green Star Design and As Built tool core and innovation points where air testing has been carried out and permeability markers achieved.
An air permeability performance or air tightness test must be carried out in order to achieve 1 point under in Credit 2 Commissioning and Tuning along with the other requirements of 2.2 Building Commissioning. Up to two additional Innovation points are available if the project is built to best practice levels of air permeability.
The current ‘maximum’ levels are conservative so achieving this point should not present problems for standard practice buildings. Aiming for a higher level of air tightness has a whole lot of other benefits including:
- Lower heat losses and gains resulting in reduced operational hours for mechanical plant.
- Reduced risk of condensation.
- Improved comfort for occupants through the elimination of draughts and cold zones.
- Reduced carbon emissions through energy reduction.
- More Green Star points.
In fact, good air tightness can deliver even better value for money as the construction costs should be lower, relying instead on improved workmanship, and the benefits are ongoing over the life of the building.
Common questions we get asked about air permeability testing for Green Star include:
- How many points should we aim for?
- What’s a typical air permeability rate for this type of building?
- How much does it cost to do an air tightness test?
- What do we need to do at the design stage to get a well sealed building?
- What if we don’t get the result we need to get a Green Star point?
- What is a good air tightness result?
ATTSA has a qualified Green Star Accredited Professional in house. You can be confident we’ll provide you with everything you need to demonstrate Green Star compliance for your project. We test to the AS/NZS ISO 9972:2015 Thermal performance of buildings – Determination of air permeability of buildings – Fan pressurization method as required by Green Star.