A façade consultant’s understanding of what air infiltration is
As we work towards carbon neutrality, and healthier and better performing buildings, air infiltration and permeability of the building envelope is becoming an increasingly important factor across multiple engineering disciplines. The terminology that these disciplines use, however, can cause endless debate. The performance requirements are stipulated in codes that use various units of measurement and measured at different air pressures. All of this can lead to confusion and potentially inappropriate specification of envelope airtightness requirements.
This presentation compares the common performance criteria and test procedures for air infiltration of façades and building envelopes. Some of these are familiar to façade consultants and contractors, while others are familiar to sustainability consultants and mechanical engineers. We will explore the requirements for air infiltration that are nominated in the NCC, Green Star, and Passivhaus, and the testing requirements of AS 4420.4, AS 4284 and AS/NZS ISO 9972, as well as how the various terminology can be interpreted. We will present real test results for key projects in Australia from laboratory testing and as-installed blower door testing.
About Robert Moisy
Robert leads the Façade Engineering on major and significant projects throughout Australia on behalf of Surface Design. Robert is the Senior Façade Engineer and team leader at Surface Design, managing the local team and international subconsultants and design office.
He has almost 20 years’ experience as a professional engineer, having started his career in Connell Wagner as a Structural Engineer working on telecommunication towers, followed by structural engineering steel and concrete structures.
He joined the Façade Engineering team to develop skills in design with other materials and assemblies such as aluminium alloys and structural glass design in 2005.
Since then, he has grown into an experienced and senior façade engineer and leader, who has completed and continues to provide Façade Engineering services to major and significant clients and projects.
Robert looks to solve our clients engineering challenges on a day to day basis as well as develop skilled and talented team members.