An off-brand cellphone charger is the focus of an investigation into a fire that destroyed a Maketū home and left a man with burns.

About 2.15am today four fire crews and an ambulance were called to a large brick farmhouse on Maketū Rd, near the intersection with Kaituna Rd.

Maketu Volunteer Fire Brigade chief fire officer Shane Gourlay said the four-bedroom steel-framed house was already well ablaze when the first firefighters arrived.

The 300sq m house and attached garage were "totally destroyed".

One of the homeowners, a 49-year-old man, was out but had suffered burns to his hands and feet, Gourlay said.

Initially, it was not clear where the man's partner was. Firefighters searched the house but firefighters did not find any sign of her.

Fire safety investigator Jon Rewi said she was later found safe.

He said the male owner had woken up in bed to blaring from the hardwired smoke alarm in the hallway.

The man initially tried to fight the fire, suffering minor burns to his hands and feet in the process.

"He didn't realise how big it was. He tried putting it out with a towel or a blanket."

The man had escaped by the time the first fire crew, from Maketū, arrived.

"If there's a message from this, it's that if you do have a fire go to safety immediately. Just get out."

Rewi said he believed the fire was caused by an electrical fault that started in the kitchen.

All early signs pointed to a plugged-in cellphone charger as the origin.

"I think it's the only thing it could be in that area."

Rewi said the charger that came with the phone was usually safe but ones bought separately or cheaply could be problematic.

A Tauranga Hospital spokesman said this afternoon that the 49-year-old man remained in a stable condition in the intensive care unit.

Maketu Fire Brigade chief fire officer Shane Gourlay the four-bedroom house, including the attached garage, was "totally destroyed".

He said more than 20 firefighters from four trucks and a water tanker were called to the scene.

It was the end of a busy night for the Maketū crews, who had earlier assisted with two medical events in the community.

Crews from Te Puke, Pukehina and Greerton were also called to fight the fire.