As part of my garage to workshop transformation I would like to convert garage door from extension to torsion springs and I would like to install a jackshaft opener. I have a standard 9'x7' door, and have a few questions in terms of what would be the best approach:

The garage door

#1. Is there a specific torsion spring conversion kit you can recommend? I have seen various different ones at different price points, but not sure which is better/worse than the other (for example https://mygaragedoorparts.com/products/torsion-springs-conversion-kit-for-7ft-high-garage-door?variant=41082462109848)

#2. Is there an easy way to determine the weight of my door simply based on its size to select the right springs?

#3. Is there a reason why the reinforcing angles on my door are not parallel with the horizontal tracks, but instead are mounted diagonally?

enter image description here

#4. I would like to install a jackshaft opener to the right (from the inside looking toward the door) of my door. I checked to make sure that I have all of the clearances and installed an outlet nearby. I had my eye on the Liftmaster 8500W, and it looks like it mounts to the wall with only 2 screws from a bracket on the side? Is this pretty typical? I would like to install some blocking inside my wall before closing them with drywall but can't quite figure out where exactly it needs to go. enter image description here

  • 1
    See that big warning. Obey it. It is one of the few warnings that I pay attention to. They are not kidding about the first line.
    – crip659
    Commented Mar 23 at 23:07
  • Look on youtube for a guide to weighing the door with a bathroom scale. There are some non-obvious steps to protect the door from damage and of course yourself.
    – jay613
    Commented Mar 23 at 23:25
  • @crip659 Noted. I am aware of the forces and physics involved and have taken the "youtube university" course on the safety aspects.
    – Yev
    Commented Mar 24 at 15:00
  • @jay613 Yes I did see that, thank you.
    – Yev
    Commented Mar 24 at 15:01

1 Answer 1


#3 The angle support is angled becase the cables coming off it could interfere with one another if it wasn't angled.

  • I've look at a lot of doors and this part seems to always be parallel with the horizontal track. I'm not sure why they didn't just shorten the cable?
    – Yev
    Commented Mar 24 at 15:02
  • Did any of those doors use an extension spring mechanism like yours, though? I've honestly never seen a door in this style that didn't use a torsion spring. (I've seen extension springs on swing-out doors, just never on roll-up ones.) Commented Mar 24 at 16:05
  • The cables definitely need clearance above the track, so they would have to be mounted higher than horizontal anyway. Once you're doing that, my guess is that it's actually more secure/stable to mount the end of the support higher as well, and there's no reason not to. Commented Mar 24 at 16:07

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.