One fell through the weakened eaves of the house, striking a colleague in the head and sending both men onto a pile of rubbish in the yard, which included metal shelves and computers.
"It was a hard landing, to say the least," said Brian Humphrey, a Los Angeles Fire Department spokesman.
The two were taken to Providence Holy Cross Medical Center in Mission Hills with injuries that weren't thought to be life-threatening.
A third firefighter suffered a glancing blow as the other two fell. He was treated at the scene, but not hospitalized, Humphrey said.
The fire, which was reported at 12:48 p.m. and took 16 minutes to put out, was in a one-story home at 9205 Dorrington Ave.
A resident told firefighters she left burning coals in metal bowls on top of a grill under a small tent or tarp structure, Humphrey said. A fire engulfed the tent and spread to the house, which was rendered uninhabitable.
The American Red Cross was helping the three adults and four children who lived there. They were not hurt.
Humphrey said there were also three animals at the home. Two dogs were out safely, but he was not sure about the third.
The fire highlights the dangers of using grills too close to houses, a problem Humphrey said is especially prevalent in colder months.