Nearly every home has them. You use them nearly everyday but not much attention is paid to the those poor springs that allow the door to open. Everyone thinks that the garage door opens because of the motor that lifts the door. It’s really that horizontal spring that sits above the door and don’t look like it doing anything. When it goes bad, no motor is going to lift that door up.
The garage door spring is balanced ever so carefully to make the door lift with the push of a finger, if there is no door opener involved. When the spring starts to go, the three or four paneled rolling garage door can collapse and be bent out of shape. That spring is very powerful and very dangerous. Anyone who doesn’t know what they are doing should mess with it. It has a safety cable running through it to assure if the spring snaps and tension is released it a somewhat violent whip-like motion. That spring is not to be messed with.
I have looked al many forms of garage door springs in my inspections. How some of them got approved or got by UL ratings, I don’t know. When our generation were kids, we played and worked around these springs all the time. Some of those side mounted springs that were attached near the hinges were very dangerous. Most of us survived to tell of it. A few didn’t. The most dangerous, of course were the single panel doors. They were every where in the 50’s and 60’s and unfortunately trapped a lot of kids under them when they swung down with force and speed. Thank God they stopped those doors from being produced anymore. Everyone has rolling panel doors now. The garage door springs are the only thing to look out for now.