By the time firefighters arrived the front of the Chartwell house was engulfed in flames.
Waikato Fire Chief Roy Breeze said the fire burned through the ceiling and roof, damaging 40 per cent of the house.
"The front is all gutted. It's got that soft-board ceiling that makes fire spread very fast through the house."
Chartwell Fire Service station officer Darren Bowler said it was too early to say what started the blaze.
He said no-one was injured but described the house as "unliveable".
Mr Bowler said he would have expected a working smoke alarm to alert the occupants to the fire sooner than they realised.
Miss Bluck, who lives in the rented house with her mother, sister, daughter and niece, said she didn't know what the family would do.
"(We've lost) half the house."
She said there were no smoke alarms in the house.