BRANZ has developed an in-depth understanding of the way moisture interacts with buildings through several research programmes. Moisture can originate from several sources including the construction stage as the building dries out or being generated by the activities of building occupants, or it can also enter through wind-driven rain or leakage.
BRANZ staff have extensive experience in dealing with all of these situations through on-site investigations, laboratory testing and evaluation and computer modelling. They have extensive expertise in detailing and laboratory testing for weathertightness. This includes:
- Buildings and moisture expertise
- Use and application of moisture and vapour barriers.
- Measurement of the water vapour resistance of materials (ASTM E96).
- Construction details for preventing condensation.
- Computer modelling of moisture risk in structures using packages such as WUFI and COMSOL.
- Thermal and moisture performance simulation of buildings and structures.
- Insulated glazing unit performance.
- Hygroscopic properties of materials.
- Field monitoring and diagnosis using environmental sensors, blower door pressurisation techniques and tracer gas methods.
We have the capability and expertise in weathertightness which include:
- Weathertightness testing of roof and wall claddings.
- IANZ accredited weathertightness testing of wall claddings to E2/VM1, the weathertightness Verification Method contained within NZBC clause E2 External moisture.
- Australian Building Code - IANZ accredited testing to FV1 - the weathertightness test method for direct-fixed, unique and cavity wall systems in the Australian Building Code. IANZ-endorsed test reports are recognised as being equivalent to test reports endorsed by the National Association of Testing Authorities (NATA) Australia.
- Advice on the prevention of rain penetration.
- Solar-driven moisture through absorptive cladding and roofing materials.