The fire was reported at 9:08 p.m. in a single-story modular home in the 4100 block of Knightsen Avenue in unincorporated Contra Costa County near Oakley.
Firefighters were unable to reach the fire as quickly as they would have liked because of reduced staffing levels at the fire district, Helmick said.
When they arrived, firefighters had to break through a locked gate to get to the blaze and then work around eight German shepherds that were loose on the property, Helmick said.
To make matters worse, there are no fire hydrants in the area and the fire district had to bring in four water tenders, each of which holds about 3,000 gallons of water, to fight the blaze, Helmick said.
Within about 15 minutes of their arrival, the back half of the house collapsed, Helmick said.
Firefighters had the fire under control in a little over an hour, but the blaze wasn't out until about 11:30 p.m., Helmick said.
None of the dogs were hurt and they have since been removed by animal control officers.
Firefighters were still on the scene this morning investigating the cause of the fire, Helmick said.