Something New in Garage Doors
davintosh.com
davintosh.com
= Oops better look for another USP, because this alternative ingenious solution has been around for years:
https://www.factoryfast.com.au/p/automatic-garage-roller-doo...
The comment about half the height of the door was in reference to how far the folded panels extend HORIZONTALLY into the garage. The folding process never goes above the top of the mechanism which looks to be less than 10 inches above the top of the door.
Not so good the first time you try to open the door somewhere snowy.
Put more simply, the door won't be able to push snowdrifts out of the way if it has to swing outward to open. Your 4x4 with snow tires will remain stuck inside the garage, unable to exit.
EDIT - After re-reading the question I now realise the comment above was about modifying this particular design to open outward at the top, and I was (incorrectly) assuming it was about a traditional outward-opening door like you might see in southern California. Sorry for the confusion. That may still be problematic, but not for the reasons I gave here.
I guess I'm not seeing the benefits for the extra complexity.
I think you misread his comment. He wasn't talking about the same kind of spring you are.
Unfortunately, they're also a bit more fragile. Speculation (mine) is that the metallurgy required to make a big torsion spring makes the material more brittle than standard spring steel. Or maybe they're just thinner and cheaper.
They sure are loud when they snap though.
I've never even seen them outside of California.
Sorry, I phrased that poorly.
There are many states where the typical California tilt-up single-piece door with levered extension springs does not meet code.
Apparently they are not secure in very high winds, so they're especially dangerous in hurricane/tornado country.
Sometimes code changes are applied at the time of sale -- either by law, by the buyer as a condition of sale, or by a lender as a condition of loan.
Pretty sure retaining cables fall into the first (by law) category, for the safety reasons you mention. It's definitely something that building inspectors look for.
But yeah, rental property is infrequently sold and almost never managed proactively.
California municipalities will come looking for property owners who fail to perform seismic retrofits, but I've never heard of anyone hunting down retaining cable scofflaws.
EDIT: I stand corrected. I went back and looked at the image (not video) I saw before. It was deceiving due to the layout but it was folding to the exterior. http://www.bifold.com/assets/slider-37.jpg
http://www.garagejournal.com/forum/showthread.php?t=197602
Vertical bifold doors are common for airplane hangars.
Also, it's basically cantilevered when retracted and should be pretty solid.
But THIS is black magic: https://www.youtube.com/watch?v=umfvm8I9_oU
This is the one that really looks like magic. https://www.youtube.com/watch?v=10y28PD73vk