A question about mould in homes could be included in the next census.
In a test census taking place next week, Statistics New Zealand will ask if there is mould in the dwelling, and whether it is bigger in total than an A4 sheet of paper.
Head of Census 2018 Denise MacGregor said it was hard to ask about housing quality in an objective way, because cold, heat, and build quality could be subjective.
That's why there is a question about mould, she said, because it's an easy question to answer.
"The question on mould is considered to be one of the best questions on housing that can be self-assessed, one of the perhaps more objective questions on housing quality and one of the easier housing quality questions to answer."
The Salvation Army welcomed the move, Salvation Army policy analyst Alan Johnson saying it would show how good or bad the country's housing stock is.
"That will give us, I think, a better understanding of where to target those responses whether it's, say, through insistence that we have higher standards or through increased insulation programmes or all sorts of other responses that might be possible."
Mr Johnson said New Zealand was too complacent about cold and damp housing.