Skip to main content.

Using AccuRate NZ to calculate the BPI for H1 compliance

Heating energy correlation graph

If you need to work out the Building Performance Index (BPI) for a house, this article shows how you can use software called AccuRate NZ to do so. A correlation between energy calculations from AccuRate NZ and from the Annual Loss Factor (ALF) method is given, and applied to BPI calculation.

More details

You can use the BPI to show compliance with the house insulation requirements of Clause H1 of the Building Code. A house complies with the insulation requirements of H1 if the BPI ≤ 1.55.

The BPI is calculated as follows:

BPI = heating energy / heating degrees total x (floor area + total wall area)

You can work out the heating energy using either ALF or another method that can be correlated with ALF.

  • Published on 15 March 2016
  • 1st edition

This information is published by the Ministry of Business, Innovation and Employment’s Chief Executive. It is a general guide only and, if used, does not relieve any person of the obligation to consider any matter to which the information relates according to the circumstances of the particular case. Expert advice may be required in specific circumstances. Where this information relates to assisting people: