BRANZ has carried out a House Condition Survey (HCS) of New Zealand houses approximately every 5 years since 1994. The 2015 sample of 560 houses was broadly representative of the national housing stock and included both owner-occupied and rental houses. The houses were surveyed between September 2015 and June 2016. The survey comprised an on-site physical house assessment, a telephone interview with the occupants and an appliance use questionnaire completed by the occupants. The questionnaire was a new addition to the HCS, commissioned by the Energy Efficiency and Conservation Authority (EECA).
The findings of the HCS have been widely used by industry, government and non-government bodies.
One of the key findings - that there are considerable opportunities for improvements in energy efficiency in the existing housing stock - is supported by other work. In its 2018 Statement of Intent, EECA estimated that more than $470 million could be saved each year by improving the quality and energy efficiency of New Zealand's houses.