Floyd Naurattel treats mould growths at a Mt Eden property. Photo: RNZ / Jordan Dunn
Mould removal companies are being kept busy in Auckland, handling double the number of calls this year to treat mouldy houses.
Experts say the wet weather has provided ideal conditions for mould take hold, but by the time you see it, it could have already been there for months, which is raising health concerns.
On a cold morning in the Auckland suburb of Mt Eden, Floyd Naurattel assessed a mould removal job in a family home like he had many times before.
Alongside his co-worker, he suited up in overalls and a protective mask to clean rooms riddled with black spots along the walls and curtains.
But it was a mild case compared to many of the jobs he was seeing at the moment.
"Yesterday, we had a visual mould inspection out in the Dairy Flats… and all the rooms had mould, due to the fact that there's no ventilation in the house."
A-Jet Services general manager Ruan Preiss said business was booming.
"It's taken off like a rocket," he said. "I wouldn't even say it's double, it's probably more than that to be perfectly honest."
Above and Beyond Cleaning Services owner Christopher Fleming said he was doing jobs at places "that have never seen mould before", and it was getting more severe.
"Some of the moulds I have been getting have been deeper in, deeper set … more mouldy than normal."
Fleming said while his company usually specialised in general cleaning, much more of the workload now was mould removal.
Restoration Specialists owner and director Tom Law said the problem was particularly bad for the owners of properties flooded earlier this year, who were only now starting to see mould appear.
"It's increased the moisture inside their properties, so with mould it's obviously a slow and gradual type of damage. They're getting on to it now."
Leon Crane (left) and Tom Law (right), directors at Restoration Specialists, are seeing requests for mould removal double after the Auckland floods. Photo: RNZ / Jordan Dunn
University of Otago senior research fellow Dr Caroline Halley said Auckland was one of the worst cities for mould growth.
"The Auckland environment, because you've got a slightly warmer, damper, more humid climate, then mould flourishes."
Its conditions were more suited to mould compared to the rest of the country, Halley said.
"It does grow in other parts of New Zealand, but with those sort of dry, cold winters it can sort of halt the growth."
She said the high rainfall since January was particularly problematic.
"The moisture you have in your home, the more mould will likely flourish. Moisture can come in through things like condensation… but it can also come in through leaks and floods in homes.
"That's probably the situation you're kind of facing in Auckland at the moment."
Halley said black mould could cause illnesses such as asthma, shortness of breath and susceptibility to colds and the flu.
She said even small amounts could be harmful, and it was important people got on top of removing mould as soon as they could.