The fire started in the basement of one home on Briggs Avenue just after 8 a.m. on Thursday and spread to another.
More than 230 firefighters and EMS responded to the scene. There were three floors on fire in both homes when firefighters arrived.
Along with the fire, the emergency responders coped with poor air quality.
"As you know, it's a very very hot day today. We are in a heat wave here in the city, and wearing all this protective gear and being encapsulated in this is very demanding on physically demanding on our firefighters," said Deputy Assistant Chief Tim Keenan, FDNY.
Five firefighters were being treated for injuries, one for heat exposure and one for trauma.
The other three were evaluated at the scene for heat and expected to go to the hospital.
Eyewitness News was there as a firefighter was taken away on a stretcher. He was awake and coherent.
"In the fire building, while they were trying to advance into the basement to get to the main body of fire, there was a very narrow, combustible wooden narrow staircase that acted like a chimney, sending blistering heat up the stairs," Keenan said.
Both buildings were heavily damaged and the residents are now homeless, but the assistant fire chief said the firefighters worked extremely hard to make sure the fire didn't spread to any other homes.
"These firefighters went above and beyond today and put themselves in those precarious and dangerous positions," he said.
The cause of the fire is under investigation.
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