Incident commander Bruno Saathof said there had been significant damage to the garage but the rest of the house had remained largely untouched except for minimal smoke and water damage.
Three fire engines from Hastings and one from Napier, and at least 16 firefighters, were used to battle the fire and ensure it had been extinguished.
Mr Saathof said the cause of the fire was being investigated but at this stage it was not regarded as suspicious. A spokesman said it was believed the fire had been caused by an electrical fault in the motorhome.
Mr Saathof said the house's female occupant was admitted to hospital early yesterday morning with a condition relating to stress.
"It was a good save in terms of the house with damage being minimal through early intervention," he said. "It's a good outcome from that view.
"The main thing is that people were able to evacuate safely and get out of the house, and their neighbours were able to look after them."
Later in the morning, fire gutted a garage in suburban Napier. The fire was reported at 5.07am at a property in McLaren Cres, Onekawa South, less than a kilometre from Hillary Cres, Maraenui, where another shed on private property was burnt on Saturday night.
A Fire Service spokesman said while yesterday's fire was being investigated by fire safety staff, it wasn't considered suspicious.
