A longtime family home has been reduced to charred rubble in west Ottawa after a Wednesday morning fire.

Ottawa Fire Services spokesperson Marc Messier said the one of the residents of 3846 Armitage Avenue in Dunrobin came home and discovered the fire.

"I had just arrived home around 9:30 this morning, and when I drove into the car port I could smell a little smoke," said Jim Davies.

Davies said said he thought it was coming from a brush fire before realizing it was his house, making sure to get his dog out before calling 911.

"By the time I called 911, I looked back at the house there was flames," he said.

Crews had to stop fighting the fire from the inside, instead focusing on protecting nearby homes and a 1000-litre gasoline tank beside the burning home.

Damage is estimated at around $500,000 to the 4,000 square foot house.

The couple that lived there said 27 years of memories are gone, but everyone is safe.

"He didn't even say it was on fire," said Susan Davies of the call from her adult son. "He said it's burnt down. I said I can't believe that."

"Everything we own is in it," Jim Davies said. "It's scary."

The homeowners said they love the area and hope to rebuild, with their two adult sons living nearby.

"I'm devastated, I loved my house," Susan said. "I just think about all the things that are in there."

Neighbours said they're devastated to see this happen to their friends, some offering to house them until they figure out what to do next.

The investigation is ongoing.

Follow Stefan Keyes on Twitter as this story develops.