OVERHEAD LIFT QUESTION

4570Man · Sep 20, 2024

scootr said:
Contact a truss builder if you insist upon proceeding they can better tell you if the trusses will support the load hung from the bottom cord. Note the truss is designed to have an even shared load from the top cord down. Hanging a load from the bottom cord is very different than the engineered application and I think there is a significantly reduced weight capacity there.

The truss builder would 100 percent say no. No manufacturer is going to accept the liability of approving this plan. And as you say the bottom cord isn’t approved for loading unless it was a floor truss. Trusses or buildings in general aren’t designed for point loads either.

Renze · Sep 21, 2024

4570Man said:
The truss builder would 100 percent say no. No manufacturer is going to accept the liability of approving this plan.

Exactly.

I built a trolley beam in my steel beam shed, engineered and all, because i know what i am doing.

But i'm not going to tell someone if its allright or not, if i havent seen the situation myself. People can add details they think is relevant, though they may miss very important details i think are relevant. And i'm just an engineer who takes pride in his work, i am not even a liable company that can be sued for telling something about their own truss building that can be misinterpreted by the customer when he adds his own contraption...

George2615 · Sep 21, 2024

Maybe just me but, I wouldn't want a 1500lb anything hanging over my head in the garage.

bdhsfz6 · Sep 22, 2024

I did what @WranglerX suggested. I use a 4 post lift in my 12' high barn:

I use the same principle to store implements in my other barn as well:

Sure, it costs more than a DIY project but at my age, saving time is worth it.
It's also a lot safer when you aren't sure of the engineering.

Just my 2 cents. YMMV.

LD1 · Sep 23, 2024

I still say a hard no as well.

I have built may garages myself. If you built yours....wheres your engineering print for the trusses? They list the designed loading as well as a CSI summary. (combined stress index). Which is usually a value under 1.....meaning that at 1.0 is the MAX design of the truss.

Alot that I see are 0.85-0.9.....meaning that without anything added they are already at 85-90% of their capacity.

And the bottom chord, unless designed for it such as an attic truss, is not ment to be weight bearing. They are in tension.....not vertical loads other than insulation and ceiling weight....which is a fraction of what a mower would weigh in a given footprint.

masscity · Sep 30, 2024

Build a shelf. You should be able to get your zero turn on top and storage for something on the bottom. I have forks, Woods

RM48 and grapple. Saves space.

rlrsk8r · Sep 30, 2024

If you look at what you all have in your “attics“ and start adding up the weights of what you have there, you’ll be surprised at how much each truss is loaded with.
I plan to bolt a piece of angle iron across three of the trusses so each trust would only “see” about 600 pounds. This includes the weight of my chain hoist. The cherry picker would be on different courses of trusses and I will span two trusses so I can get the main spine of the picker between them and gain additional height from the floor to the horizontal legs. The attic floor does not go all the way to the wall of the building.

Sandman, I fully understand the failure of your bar joist and not at all surprised at its failure. They’re very strong vertically, but essentially have no strength laterally.

Also, I had not thought about the three post corner lift which is a viable option for me at this point. I’ve been building 3 foot wide industrial shelves 4 feet from the back wall of the building and 7 feet from the sidewall. I could eliminate my first course of shelves giving me an additional 3 feet of clearance from the side, and back the Zero under the head of the frame. By the way, when I lift it all the way up, I will have almost eight feet of clearance from the floor.

The bottom chord is a 2 x 10 and the plate that I am bolting to it to support my angle Iron will be 2 inches from the top of the chord. Rather than putting a lag bolt going up, I will have 3 ears welded to the angle iron going up, parallel to the side of the chord, drilled for a half inch bolt going through the bottom chord near the top of it. This way, I will have 7 inches of wood under the bolt which will effectively be loading the chord from the top. Where the 1/2” bolt comes out of the wood, I will have a steel backing plate that is 3 in.² and will be torqued to about 100 foot pounds.

And, LD1, it is designed as an attic truss. It’s 30 feet long with a 20 foot wide attic. Hence the bottom chord is a 2 x 10. This suggests to me that I can hang my 1500 pound mower from three of the chords.

leonz · Oct 1, 2024

Roof trusses were not designed to carry a loading like this, they were designed to support the roof and support the roof in the event of a heavy snow load. You will rip out the truss bottom planks and then you have to have the truss fixed and then certified as safe.

Putting the mower in a mower sized hoop shed will be less work and you can still drain the fuel tanks, remove the battery, remove the air cooling shroud on the engine to prevent mice from using it as a nest.