Mobile homes offer lower-income families respite from California’s housing crisis but a fatal fire has underscored their potential as death traps.

A suspected candle or Christmas tree lights ignited a conflagration whose speed and ferocity claimed the life of a five-year-old girl and injured eight relatives in Escondido, in San Diego county, on Thursday.

The fire erupted shortly after midnight in the home of the Flores family at the Greencrest mobile home park, trapping some members inside while others escaped through windows, their pyjamas aflame.

“Mobile homes just burn faster than regular homes,” said Escondido fire battalion chief Russ Knowles. “In a regular home you have … framing and dry wall that can provide some protection and slow down the fire. But in mobile homes there is typically just panel sheeting. So it’s very common that we see them burn a lot faster. That reduces residents’ time to get out.”

The tragedy came amid further signs of a febrile property market which has driven up rents and homelessness across California. The value of homes in San Diego county reached $596bn in 2016, up 6% from the year before, according to a study by real estate database Zillow. Renters spent $9.6bn this year, up 8%.

Many lower-income families find refuge in mobile homes and recreational vehicles – avoiding the fate of the 78,000 people who live outdoors in California. Another 40,000 live in shelters and other transitional accommodation, according to the department of housing and urban development. Over a third of students in the school district which includes East Palo Alto, in the heart of Silicon Valley, are defined as homeless.

Three generations of the Flores family – six adults and four children – lived in the mobile home. Nine were at home when the blaze erupted.

“The cause is undetermined but we’re pretty sure it was electrical in nature, or a candle,” said Knowles, the fire chief. The cable or extension cord of Christmas tree lights were possible candidates. The absence of smoke detectors meant the family slept while toxic fumes and superheated air spread through the confined space, he said.

Neighbours woke to the sound of the family screaming.

“People were coming out of the windows in bare feet and in their pyjamas and smelling like burned plastic,” a neighbour, Cristina Zazueta, told the San Diego Union Tribune. “It was awful, just awful.” The house kept “bursting” with popping noises, she said.

Sandra Flores, 25, the mother of the dead girl, who has not been officially named, was distraught and screaming “get them out”, referring to children trapped inside. “I asked her where the baby was and she said she had no idea. I asked where her brother was and she said it was too dark to see,” said Zazueta.

Sandra’s father emerged with “smoke puffing off his body”, said the neighbour. She held back those who wanted to enter the inferno. “It just kept popping and I was nervous that there would be some bigger gas burst. You could feel heat popping out of the house. Everybody was standing so close so I kept grabbing them to keep them away.”

The house “lit up”, with fire coming from every window, said Zazueta. “I didn’t know what to do. All I could do was retreat them away from the house as best I could.”

Firefighters risked their lives to suppress the flames and try to save those inside, said Knowles. “We see a lot of different things throughout our careers but nothing is more dramatic than putting out a structure fire and have people yell and tell us there are people trapped inside. We have to set aside emotions and focus on the job.”

The eight survivors were treated for smoke inhalation and other injuries.

A Gofundme.com page set up by a friend to help pay for funeral and medical costs swiftly exceeded its $30,000 target. Donors called the family sweet, kind and hard-working.