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Garage door design is weak


John Kogel

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This 20 year old townhouse has a busted window in the wooden garage door. Not surprising.

My client wants the sellers to fix it. I said the frame is broken and needs to be repaired, or replace the door. Strata council will demand that the new door look just like this one.

Should the opener be moved to line up with one of the upright frame pieces?

Or would a metal brace screwed across the top take care of it?

I've seen both and am wondering what's the better way to go.

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You say the frame is broken. I can't tell from the photo, but is that top rail cracked at the attachment point?

Openers are supposed to be attached to the center of the door, so I would not move it off to one side as that could cause the door to rack. A sizable piece of angle or channel iron would be my own fix (as in Marc's photo) but I wouldn't try to specify anything in particular, rather have them get a garage door contractor to correct it.

Any extra weight can and should be be easily accommodated by adjusting the torsion bar/spring. One re-balanced, the perceived weight at the opener would be the same. It's not going to get too heavy.

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Agree with Richard,

Center is best, but if a torsion spring is properly balanced side to side you can connect them anywhere and it really doesn't make that much difference.

The opener doesn't really lift much weight because the door is supposed to be neutrally balanced by the torsion springs.

I'd bet that door broke because the down-force is set to high, the door encountered an obstruction and when the door stopped the opener continued to push, causing the top of the door to flex and the glass to shatter.

Get the down-force and close/open limits properly adjusted, add a stiffener along the top, replace the glass, adjust the torsion springs to accommodate any additional weight, and it will be fine.

ONE TEAM - ONE FIGHT!!!

Mike

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You can't adjust a torsion spring. The spring is sized to the weight of the door by altering the wire size, the diameter of the spring, and the number of coils. The spring gets wound 1/8 to 1/4 turn beyond 1 full turn per foot of door height to balance the door.

That is a small door, adding a strut or perforated angle to the top rail won't add enough weight to make a difference to the spring or the opener. Add a strut per panel and the door will no longer balance but the opener will likely still work fine, though the plastic gears will have a slightly shorter service life.

Greg, there is a bracket for doors that don't have a center stile, but it doesn't work on doors with windows in the top panel. [;)]

Mike is right about the down force, it's too high, and the bottom limit is probably wrong too. With a torsion spring that opener can be anywhere but above a vertical stile is preferable. I have a client that has one opener centered between two doors, it's been opening both for over a decade.

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You can't adjust a torsion spring.

Well, gosh dang it. I wonder how come that frigging garage door guy took money from me claiming to adjust the torsion spring to balance the door.

Guess I'm gonna call him and demand my money back!

[:-paperba[:-paperba[:-paperba

-

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This is a good example of why we should not design the repair. Just report that the window is broken/door is broken or whatever the case is. Then report that they need to contact an overheard door/garage door specialist for the proper repair, which could and will most likely involve the replacement of the door.

It looks like the door is missing a support bar/bracket and this is what has caused the problems. The door is flexing due to the lack of proper support.

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Thanks, all. "Vertical stile" gets filed away somewhere where there are still live brain cells, thanks Tom. I get your meaning on the spring, it is what it is, but is it not wound to the required tension?

My question is not so much about designing a repair, I try not to drift that way. But I may need to advise the client afterwards if the repair she got is adequate.

It looked to me like a finger-jointed piece of wood was expected to perform like a clear piece.

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If the door is balanced with the opener disconnected, meaning that it will stay put when it is around half way open, then the spring is properly wound. If the spring is under wound the door won't balance and the cables will go slack and fall off the drums as the spring stops turning before the door completes its travel. Over wound the door will runaway as it approaches fully open, and if over wound enough may drift open on its own or dangerously out travel the length of the horizontal track.

A torsion spring exerts a varied effort on the door as it moves to support only the weight that is in the vertical section of track. With the door closed the spring is under full tension, then for each foot of travel as the door opens the drums make one full turn (and therefore so does the spring) reducing the amount of energy stored in the spring and the amount of weight it will carry. The extra 1/8 to 1/4 turn is there to maintain some tension on the cables when the door is in the fully open position so that they rewind properly as the door closes. Wooden doors complicate the spring calcs because they are never a consistent weight from one door to the next, and that weight changes as frequently as the weather.

The down and dirty fix for that door is to bolt on a piece of perforated angle that is at least 50% longer than the distance between the vertical stiles, preferably as long as the door. The proper fix is to have a new panel fabricated and installed with a steel strut across the top rail. In either event the opener needs some serious adjustment. A properly adjusted opener just doesn't generate the force to pop a finger joint like that, even if the seller closed it on her car (an educated guess).

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Thank you, sir. The sellers are away, so I trust the garage door company named on that decal will perform the task. I hope they know their biz.

Now if there's a callback to me, I'll pass on this info.

The door has operating electric eyes at the correct position, and auto-reverse seemed to be OK, so how the damage occurred is a mystery. Maybe they repaired the eyes afterwards....

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You can't adjust a torsion spring. The spring is sized to the weight of the door by altering the wire size, the diameter of the spring, and the number of coils. The spring gets wound 1/8 to 1/4 turn beyond 1 full turn per foot of door height to balance the door. . . .

I have done reinspections of doors that were not properly balanced during the original inspection (when I lifted them 3-4 feet off the floor and let go, they slammed to the floor). When I returned for the reinspection, the doors were properly balanced. I'm sure, in those cases, that the torsion springs were simply wound tighter.

So, what's the downside to this? Is this one of the reasons that torsion springs break?

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