Claims Auckland's problems with "ghost homes" may be overstated

Around 40-thousand houses in the city sat vacant during 2018 Census night - an 18 per cent increase since 2013.

Council planning committee chair Chris Darby says it's a significant number of habitable homes not being utilised.

But Housing Minister Megan Wood says houses could be recorded as unoccupied in a Census for many reasons.

That includes homes being under renovation, between tenants - or that the owner was simply away for the night.

She pointed to a 2015 study by electricity company Vector, which suggests eight-thousand homes were left empty.

That meant they'd used less than 400-watts of power a day for 100 days.