Melbourne grandmother lucky to be alive after ceiling collapses on her bed

A Melbourne grandmother is lucky to be alive after her bedroom ceiling caved in on top of her while she was in bed.

The 90-year-old was trapped underneath plaster and insulation after the roof collapsed at 5.30am at the home in St Albans in the city's north-west.

"Mum heard a loud crash," the woman's granddaughter Teresa, who didn't want to give her last name, told 9News.

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"She said to come over, 'The roof's collapsed and grandma's stuck inside."

"Grandma was yelling out saying, 'Help me, help me'."

Teresa and her mother couldn't open the bedroom door and called emergency services.

Emergency services were there within minutes, armed with a ladder and bolt cutters.

They got grandma out, without even a scratch.

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She just had a sore neck from the pieces of plaster that hit her.

The family joked they needed to buy a lottery ticket after her remarkable escape.

The family is still unsure what caused the collapse, but had noticed a crack in the ceiling the day before.

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"We didn't see any water marks, anything like that, only thing was a crack in the corner, that's why we called insurance yesterday," Theresa said.

Despite the significant damage inside the front room, from the outside it's hard to tell anything happened.

However, until insurance assessors take a look, the family say they're too worried to stay in the home.