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Weathertightness testing

Roofs, walls, windows and doors must be weathertight to prevent leaks and damage caused by moisture. BRANZ can evaluate weathertightness through laboratory-based and on-site tests of air permeability, watertightness and wind resistance.

Testing methods

We use a range of methods to evaluate the weathertightness of roofs, wall claddings and other external openings such as windows, doors, meter boxes and pipes. Our testing capabilities include:

  • measuring the water vapour resistance and hygroscopic properties of materials (to ASTM E96)
  • computer modelling of moisture risk in structures
  • assessing insulating glass units (IGUs)
  • testing of assemblies under the combined action of water and wind pressure
  • field monitoring and diagnosis using environmental sensors, blower door pressurisation techniques and tracer gas methods.

Standards we test to

BRANZ can test to a range of standards. Many are accredited by International Accreditation New Zealand (IANZ).

Windows and doors

We are accredited by IANZ to test windows and doors to the following standards:

Assemblies and structures

We test to the following standards for windows, doors, wall claddings, floor and ceiling panels in accordance with AS/NZS 4284:2008 Testing of building facades:

  • Structural test at serviceability limit state air infiltration test
  • Water penetration by static pressure (and as modified by E2/VM1 (7/04)) test
  • Water penetration by cyclic pressure (and as modified by E2/VM1 (7/04)) test
  • Wall claddings to E2/VM2 Cladding systems for buildings up to 25 m in height - including junctions with windows, door and other penetrations
  • Australian Building Code FV1 Weatherproofing - the weathertightness test method for direct-fixed, unique and cavity wall systems
  • Roof weathertightness testing to AS 4046.9-2002 Methods of testing roof tiles - Determination of dynamic weather resistance and to many of the international (ISO), European (EN) and American (ASTM) standards using variations of air pressure difference and water application rates.

About IANZ endorsements

IANZ-endorsed test reports are recognised by regulators in countries where accreditation authorities are signatories to the International Laboratory Accreditation Cooperation (ILAC) or Asia-Pacific Accreditation Cooperation (APAC) Mutual Recognition Arrangements. They are equivalent to test reports endorsed by the National Association of Testing Authorities (NATA) Australia.

Enquire about weathertightness testing

For more information about our weathertightness testing services, contact us by:

Updated: 16 October 2023