The cause of the house fire that forced a family of five from their home after midnight is under investigation today.

The family noticed the fire in their Te Hono Street home about 12.30am, when a fire in the garage spread into the main building.

'The garage is destroyed, There's a reasonable amount of structural damage to the house, maybe 20 per cent, but we kept the house reasonably smoke free,” says Tauranga Senior Station Officer Mark Keller today.

The owner of the house woke up and realised there was a fire down in the garage and then saw the fire was actually spreading towards the house and filling the house up with smoke. The garage was detached but close enough to spread into the house, says Mark.

'We had three trucks initially but the fire was spreading rapidly through the roof void I was running out of BA crews pretty quickly, so we made it a second alarm so we ended up with six trucks there.

'Four crews, eight men working in BA were able to stop the fire in the roof void, because we were able to make entry though the house and hold the fire from spreading from the garage.

'Then the worst bit was because it was going everywhere. It was a two storey place, the lower section of roof went right round the structure and the fire was breaking out through the interior walls upstairs. So we had a crew upstairs, and we had a crew at the garage and then two crews working the roof area.

'So it was pretty busy there for a while but we were able to stop it pretty much – apart from the damage in the roof – we were able to stop it pretty much where it was when we got there, so that's always a plus.”

The cause is unknown. There was no real indicator to fire crews about how it started.

There was a scene guard on the house overnight and a fire investigator was at the house this morning.

The house today. Photo: Tim Follett.