The massive five-alarm blaze triggered a five alarm response from the Houston Fire Department.
"There are about 150 firefighters currently working to get this fire under control," said HFD Captain Ruy Lozano.
That number would grow to more than 200.
It was an intense fight against the raging flames and the heat, which became almost overwhelming at times to firefighters draped in full gear.
"It was hot," said one firefighter who said he had been on the force for about five years. "You could feel it all the way from here on this side, all the way to where that other ladder truck is on that side."
The searing heat forced portions of the building to give way.
"Because it was under construction, a lot of things were exposed and we're having a lot of collapses of the construction in different areas," added Lozano.
Firefighters pulled a construction worker to safety and took stock of an intense fight they don't often see.
The dramatic rescue was all captured on home video shot by Karen Jones:
The worker is seen standing on the floor of an incomplete patio. He waves for help as flames draw closer, then dangles his legs over the edge, swings and drops to a fourth-floor ledge.
A firefighter on an extension ladder reaches the worker. The worker reaches and crawls to the ladder just moments before a burning section of upper wall collapses next to them.
The ladder then draws the worker and the firefighter to safety.
Investigators are trying to determine whether the fire was started during welding.
Amazingly, no one was injured in the fire.