A stove fire in a third floor unit started the inferno at the 1600 Church Road condominium complex.
The fire marshal says the resident tried extinguishing the burning oil in a pan, but fled once flames spread to the kitchen cabinets
Officials say the fire started just after 9:30 p.m.
The fire started in the "B" building also known as the Beacon Building which is the largest building on the property with 55 units.
20 fire companies and 125 firefighters worked for more than four hours to get the fire under control.
Five residents and two firefighters were sent to hospital with non-life threatening injuries.
"The crews came in and tried to fight the fires from the interior, made it into the room, but the fire was already into the hallway," said Glenside Fire Chief Joe Stuckert.
Chief Stuckert said that several residents had to be rescued; some treated for smoke inhalation.
"It was just a lot of smoke then you saw flames, then it just kept going on and on and on forever," said Sylvia Bennett.
Officials say half of the roof on the building collapsed.
A crane was brought in Saturday to tear down the portion of the building with the worst damage, and crews turned off gas and electric to the entire complex.
Three other buildings in the complex with 40 units each were evacuated for safety reasons.
Cheryl Rivers' cousin lived in the building. She was out of town at the time of the fire, and has not seen the damage to her home.
"I wanted to see if she could salvage something when she gets in tonight," said Cheryl. "She'll be flying in tonight."
"I heard some of my neighbors in the hall, and when I looked out I saw smoke and I thought, 'it's real', let me put my clothes on and get out, thinking I would be back in an hour," said Angela Hollis.
Angela Hollis lives next to the Beacon and is staying with family and getting help from her church.
"It's one day at a time at this point. I'm just grateful I walked away with my life. Everything else can be replaced," said Hollis.
The Red Cross said 37 people sought assistance after the fire .
"The Red Cross provides the emergency relief efforts but we can't do it alone, we can't do everything," said Dave Schrader. "We depend on the community to rally around disaster victims to help them recover, and that's what was going on today."