The National Construction Code 2019 introduced compliance of building envelope sealing or blower door testing in section JV4. This verification method requires a mandatory building air tightness test to be conducted according to Australian Standard 99:72 on all buildings.
Compliance with Section JV4 requires a building to not have an envelope permeability larger than 5m3/h/m2 or 10/m3/h/m2, depending on the building classification and climate zone.
Air tightness testing has been used in many other countries to verify energy models, reduce energy consumption and prove compliance with building permeability regulation. The carbon neutral by 2050 target set by COAG has put the federal and state governments on notice to investigate all options that reduce energy consumption. Building envelope leakage is a simple and highly effective first step in moving towards building energy efficiency, and is predicted to become integrated as an energy reduction tool for all construction in Australia.
Navigating envelope code compliance is an expensive and time-consuming process for designers and builders alike. For this reason, Aerotight offer guidance during each project for all our clients to ensure their team understand the concept of building air tightness and develop identification skills to avoid expensive mistakes.
Aerotight have the equipment and experience for testing a large-scale commercial buildings and have been offering workshops, consulting and compliance testing for our clients for over 10 years Australia wide.
JV4 Building envelope sealing
Compliance with JP1(e) is verified when the envelope is sealed at an air permeability rate, tested in accordance with Method 1 ofAS/NZS ISO 9972, of not more than:
(a) for a Class 2 building or a Class 4 part of a building, 10 m3/hr.m2 at 50 Pa reference pressure; or
(b) for a Class 5, 6, 8 or 9a or 9b building, other than a ward area, in climate zones 1, 7 and 8, 5 m3/hr.m2 at 50 Pa reference pressure; or
(c) for a Class 3 or 9c building, or a Class 9a ward area inclimate zones 1, 3, 4, 6, 7 and 8, 5m3/hr.m2 at 50Pa reference pressure.
If your building has a Section JV 4 requirement and you want to know more, get in contact with Aerotight to develop your pathway for NCC Section JV4 compliance.
6 steps to air tightness compliances
Building air tightness is a concept that starts at design, is implemented during construction and confirmed with a test at the end. The performance benefits obtained from having an airtight envelope can only be realised if both the design and construction teams understand what the target is, what the correct construction materials to use are, and how to manage the installation.
The concept and techniques of air barrier construction are universal to all projects, however the methods and solutions to build air tight need to be tailored to each project. For this reason, Aerotight have developed a workshop program to assist new design and construction projects in understanding the requirements and building towards their air tightness target.
Our recommended steps to fulfilling a building air tightness specification:
Step 1 - Envelope performance
Step 2 - Define the Air barrier
Step 3 - Material Performance
Step 4 - Construction Performance
Step 5 - Air barrier inspections
Step 6 - Testing
Contact Aerotight for more information on our services