0

enter image description here

I want to hang this pulley system in my garage (partially pictured above) and probably will be loading it up somewhere between 100-200 lbs of plate weights:

https://www.spud-inc-straps.com/econo-triceps-and-lat-pulley.html

What is my best option? Putting a 2x4 across multiple trusses with lag screws and hanging from that? Doubling up some studs and building out some kind of arm support system? Some other option I am not aware of? I am not familiar with how much additional weight (beyond keeping the roof up) either of these two options can support and don’t want to cause any kind of structural damage, to the garage or myself! Thank you.

4
  • 1
    Spreading the load across multiple rafters is a good idea. The closer you position your pulley to the bearing wall, the less the rafters will flex.
    – Charles
    Dec 24, 2019 at 17:38
  • Yes, I’d like it as close as possible to the wall while accounting for the diameter of the largest weight plate and some wiggle room for any swinging. I will be yanking on it. Dec 24, 2019 at 18:44
  • You may also want some support from below it looks like 2’ on center to me, I would want to span more rafters also like @charls suggested.
    – Ed Beal
    Dec 24, 2019 at 20:04
  • Based on what we can see in the picture, there are no obstructions to sistering two of the existing ceiling joists -- adding a second 2x4 in parallel to an existing one, and nailing them together, to increase the load-carrying capacity. If there's nothing else blocking you from doing this out of the frame, it'll only cost you a few dollars for two 2x4s and some nails. Search online for sistering a joist for illustrations to help you decide if this is what you want to do. Sep 22, 2020 at 16:30

4 Answers 4

1

Put the load right at the wall

The carrying capacity of beams is much stronger right next to a vertical support. So put your pulley as close as possible to the wall, so all the downforce is there. And also use the multiple beam-spanning idea - however that is only as good as the stiffness of your spanners. If you have the height, use a 2x6 on edge.

But don't pull the building over

The roof truss may be stiff, but what keeps the opposite walls from going paralellogram when you put sideload on the ceiling truss? I would run a string diagonally from the bottom of the opposite wall to a little eyebolt "pulley" at the top of this wall, then straight down to a weight. Put a dot with a magic marker on the string. Watch it as you exercise, and see if it moves. If it does, you're tilting the whole building and it's time to stop!

0

I'd go with the 4x2, those trusses each look sufficient to hold a 100kg or more,

Spreading the load won't hurt, place the 4x2 above the bottom chord of the trusses and use nails or screws to hold it in place,

2
  • Thanks Jasen. Can I expect 100kg to multiply across trusses? For example, 4 trusses = 400kg? That’s about 4 times the max weight I’d ever be lifting, so perhaps across 2 trusses (200kg) would be sufficient, as I won’t fool myself and say I’ll ever even be loading this with 100kg. By the way, for my own knowledge, how do you estimate how much weight a truss can hold? Is this some math I can do, or just an estimate from experience? Thanks! Dec 24, 2019 at 18:48
  • you could look in a framing manual, but that 100kg is just a guess based on the aparrent thickness of the timber in the bottom chord of the trusses. I'd expect to be able to swing off one of those trusses and not damage it. being wood it's going to flex a bit before it begins to break so if you put the beam across 4 trusses the middle two will get most of the load, but the outer ones will also get some of it.
    – Jasen
    Dec 25, 2019 at 3:30
0
  1. If the pulley is going to be used for slower movements. Then just beef up your wall with a couple of 2x6s and attach it to the top of the wall. Not the truss for sure. I have damaged joists/trusses with things I used for lifting and boxing. They flex too much even if beefed up.

  2. If you are going to make quick/jerky thugs then you really need to use the corner. I would run a couple of 2x6s across the corner and attach the pully to the hypotenuse. You are going to have to beef it up but a corner should deflect the movement better than attaching to one wall.

0

Put a 8' 4x4 or 2 2x4s above the truss bottom cord. Toenail some screws into truss to stop from shifting. Your main concern should be not damaging/splitting the truss's 2x4s with lags/ structural screws.

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.