What is AS/NZS 4859.1?
AS/NZS 4859.1 is a standard that outlines the general criteria and technical provisions of thermal insulation materials for buildings.
How is it Changing?
The updated AS/NZS 4859.1:2018 standard will see changes introduced to the way the product is tested and how thermal performance (R-value) is calculated and declared, affecting bulk, reflective foil and rigid foam insulations.
The biggest changes within the amended standard AS/NZS 4859.1:2018 are to do with thermal testing and formal declarations of performance labelling.
Thermal Testing:
- A statistical assessment of at least 10 test results is required for each material assessed under the standard.
- This statistical assessment shall determine the R-value and thermal conductivity for the products tested from the statistically adjusted mean values representing a 50% fractile with 90% confidence for a one-sided tolerance interval. To be expressed as R50/90 or λ50/90.
- The same statistical assessment is applicable for all insulation materials, except for vacuum insulation panels.
- The adopted heat aging methods required for determination of long-term thermal values for rigid foam insulation materials are now aligned with European standards and are more stringent than before to more accurately represent long term in-situ performance:
