Please read the instructions before using the tool.
Compliance requirements for H1/AS1 5th edition amendment 1
The use of H1/AS1 5th edition amendment 1 is restricted to housing, or buildings other than housing that are less than 300 m².
Buildings with curtain walling are excluded.
New methods for determining the thermal resistance and construction R-value of building elements are contained within H1/AS1 5th edition amendment 1 and include methods to calculate the R-values for slab-on-ground floors, windows, doors and skylights.
NZS4218:2009 is no longer referenced within H1/AS1 5th edition amendment 1. Other standards have been added.
The climate zone maps have been revised to include six climate zones.
Using the schedule method, the window area of the building can be no greater than 30% of the total wall area. (The calculation method can be used where the window area is up to 40% of the total wall area; for glazing beyond this, the modelling method must be used.)
Where heating is embedded in a building element, a higher minimum R-value is required. See H1/AS1 5th edition amendment 1 for details.
Please refer to H1/AS1 5th edition amendment 1 for full compliance information.
This tool cannot be used for H1/AS2 1st edition, which deals with larger non-residential buildings which have different requirements.
Using the tool
Select the climate zone and accurately enter all the relevant areas.
Data should only be entered into areas that are shaded in blue.
Cells that are shaded in dark blue provide a dropdown list of options. Only options from the dropdown list can be used.
Calculated cells are shown in orange and cannot be selected.
The print area has been set to cover the white area on the sheet with the print orientation for the Overall sheet is set to portrait and the print orientation for the By-Element sheet is set to landscape.
Measurement of areas
Refer to H1/AS1 5th edition amendment 1 for definitions of building element areas and how to measure them.
The designer should verify the construction R-values for the various building elements. These are NOT the same as the insulation R-values.
Use the BRANZ House Insulation Guide 6th edition to find construction R-values or use the appropriate methods to calculate the construction R-values:
- For walls, roofs and floors other than slab-on-ground floors, use NZS 4214
- For windows, doors and skylights, see Appendix E in H1/AS1 5th edition amendment 1
- For slab-on-ground floors, see Appendix F in H1/AS1 5th edition amendment 1
Interpretation of H1/AS1 5th edition amendment 1
This tool is implemented according to an interpretation of H1/AS1 5th edition amendment 1.
Limitations and liability
BRANZ Ltd accepts no liability for loss or damages resulting from use of this tool.
The accuracy of the calculation relies on the designer entering accurate values.
Restrictions on use
This tool is only to be used in its full, unmodified form.