A massive fire that gutted a popular Hamilton restaurant was caused by a stack of hot tea towels spontaneously combusting.
It took firefighters from across the Waikato about 90 minutes to bring Friday's early morning blaze at Domaine Eatery on Victoria St under control.
Smoke could be seen billowing across the city as more than a dozen fire appliances were at the scene.
Waikato fire safety officer Kevin Holmes confirmed to the Herald this afternoon the blaze was caused by the "spontaneous ignition of oil-contaminated tea towels" which had been just pulled out of a dryer and left in a basket in the rear of the restaurant.
"Over time, tea towels used in a restaurant maybe used to wipe down bench tops or cooking pots in the kitchen and pick up cooking oils. That's built up over time and if they're just washed in cold water all the time the oil can stay in the cloth.
Then when they go through a clothes dryer, on this particular occasion they were taken out and put in a basket still warm."
Mr Holmes said the basket was put near the kitchen in a doorway to a little cupboard at the foot of the stairs that leads to a mezzanine floor in the rear of the restaurant about 9.30pm on Thursday.
"So what happens there you've got a basket of contaminated tea towels in it that have come out of the clothes dryer still warm so it's spontaneous ignition, you get what's called a thermal runaway, so it's a chemical reaction. Because it's so hot inside that pile of tea towels they can spontaneously combust, which is caused by the oil, but it has to be a vegetable-based oil. On this occasion it's most likely cooking oil."
Mr Holmes said the blaze was a timely reminder for not only restaurants but laundromats to always use a hot wash when washing their tea towels to ensure all the oil is cleaned off.
He said it was also imperative that items in a dryer be allowed to run their full cycle into its cool down cycle so that it cools down whatever is inside.
Mr Holmes said fires caused by tea towels spontaneously combusting were not common but had happened before.
Domaine Eatery owner Jeff Dunstan said the cause of the fire was "totally freakish".
"I have never heard of it before. It's definitely a shock to know that it can happen anywhere, anyhow, but I suppose the more people that are aware of it the better and the less it will happen as well ... we've all got dryers and so forth and everybody uses them like no tomorrow, especially in the winter."
Mr Dunstan said five days on since the blaze, yesterday had been the hardest as it was his first time walking through his beloved restaurant with an insurance assessor looking at the damage.
"It was hard to see everything you've worked for and dreamt of and yeah, it's gone."
As for rebuilding, Mr Dunstan was keen to get it back up and running.
"I definitely want to. Whether it's something like that or something similar but it might be down-sized at this stage. I'd love to be in the same spot because that's where Domaine is. But it's early days yet, I'm not quite sure where we're going, what we're doing, so everything's still up in the air. But hospitality is in my blood, I love seeing people walking out happy. That's what it's about."
Mr Dunstan said he has been humbled by all the support from not only family and friends but others in the hospitality industry.
As for his staff, he had found some of them other part-time work, but the more senior members were taking it hard.
"One of them, he's my right hand man, he's gutted and hurt ... and another has been there for 14 years so most of them, yeah, were beside themselves."
Mr Holmes said the fire was purely an accident.
He had attended a similar incident at the premises of a sports massage therapist, who operated from home.
Over time her towels had accumulated oil from the various massages.
"She used to take them out of the dryer before they went through the cooling stage and roll them up and put them in the hot water cupboard because she said by doing that the towels remained soft. And the same thing happened there, spontaneous combustion."