BRANZ H1 Calculation method tool - 6th edition
- Abbreviation
- BRANZ - H1 Calculation method tool, 6th edition
- Version
- 6th edition
- Valid from
- 3/12/2025
- Information provider
- BRANZ Limited,
- Author
- Building Research Association New Zealand Ltd.
- Information type
- Tool,
- Format
- Website,
Description
This tool checks for compliance of housing and small buildings with the calculation method of H1/AS1 6th edition.
Inputs are added on separate sheets, and a results page is automatically generated, which can be submitted for compliance.
To input data and generate results on one sheet only, use the H1 calculation method tool - Basic.
There are two calculation methods:
- H1 Calculation method tool [Full] This tool automatically applies the calculation method of H1/AS1 6th edition and generates a results page that can be used to demonstrate compliance.
- H1 Calculation method tool [Basic] This basic tool checks for compliance of housing and small buildings with the calculation method of H1/AS1 6th edition.
Scope
Compliance requirements for H1/AS1 6th edition
The use of H1/AS1 6th edition is restricted to housing, or buildings other than housing that are less than 300 m².
Buildings with curtain walling are excluded.
Methods for determining the thermal resistance and construction R-value of building elements are contained within H1/AS1 6th edition and include methods to calculate the R-values for slab-on-ground floors, windows, doors and skylights.
The wall glazing area (windows and glazing in doors) of the building can be no greater than 40% of the gross wall area.
Roof, walls and floors other than slab-on-ground floors must meet certain minimum R-values.
Heated ceilings, heated walls, and heated floors must meet certain higher minimum R-values, except where they are solely installed in rooms with a shower, bath or toilet.
Please refer to H1/AS1 6th edition for full compliance information.
This tool cannot be used for H1/AS2 2nd edition, which deals with larger non-residential buildings that have different requirements.