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How much could I lift?

Ultradog MN

Cast Iron
Joined
Jun 14, 2020
I will finally be getting the drywall in the ceiling of my garage this summer.
Would like to put a lift point in it before the drywall goes up.
Trusses are 2' on center.
I would add a 10" LVL beam on each side of two of the trusses. Screw the beams to the W bracing in the trusses.
How much could I lift?
Hope the drawing is readable.
 

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Probably not as much as you'd like, since trusses are designed for mainly compressive loads. The cleats (plates) used for truss construction mainly just hold the lumber in position while the compression load is distributed by the butt of one segment to another. Loading from the lower half of the truss applies tension to some of the plates, and some of them often aren't very big. I'll be interested in what the 'experts' have to say.
 
I will finally be getting the drywall in the ceiling of my garage this summer.
Would like to put a lift point in it before the drywall goes up.
Trusses are 2' on center.
I would add a 10" LVL beam on each side of two of the trusses. Screw the beams to the W bracing in the trusses.
How much could I lift?
Hope the drawing is readable.
Well,
Judging by the lack of responses this place might not have been the best place to ask this.
(And I thought you guys knew Everything)
So, can anyone recommend a site where a guy could get that kind of info?
Thanks
 
Well,
Judging by the lack of responses this place might not have been the best place to ask this.
(And I thought you guys knew Everything)
So, can anyone recommend a site where a guy could get that kind of info?
Thanks

I thought someone else would answer. What sort of weight are you *hoping* to lift? Can you get inside the existing wall to add extra bracing under the sill plate? As it stands, the 4" square, 1/4" wall tubing @24" length is going to be the strongest link in your chain. The lam beams look like they aren't going to be safe with much more than maybe 350 pounds at that length and height. The roof truss might add a little, but I wouldn't push it. You'd need to make them taller to help much and/or add multiple laminations, and then watch out for the sill plate. As it stands with your specs, I think 350 pounds would be a safe limit.
 
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You could abandon the gluelam beams and make a couple of steel trusses the same size as you existing roof trusses. I would use 2x3x.120 tube for this.
Easier would be to just put an 18' I-beam up there but you may need to add supports in your room if the beam is to tall to get on top of your top plate without poking through the roof. ;)
 
Sorta OT, but unless you're looking to butcher a deer, I can't see where a stationary lift is of much value. Anything you lift can only be as heavy as your best cart can handle. (For moving the load after the fact.) Then once you roll it over to the machine, now how do you get the load off the cart into the machine? What you need is a well designed Cherry Picker.

I got a 1/2 ton years ago. Cut off the legs and stubbed them out 4". Now it will straddle any Knee Mill and many CNC main castings. Also has an 18 inch lift cylinder which has come in handy more times then I can count. Three pin-able height extensions and four length ones. Handiest damn shop hoist ever. Think about it... besides... does engines too! :-)
 
In California you would add shear wall plywood to the trusses. nails every 2-3 inches on the edges every 12 " in the main body. This will add. a lot of vertical strength as long as it goes from side to side and clear to the peak. Good luck getting the pieces in there.
This kind of makes it a giant I beam or drag truss
Bill D.
 
LVL manufacturers provide load tables however the problem is they are usually in lb per foot which doesn't help you because if you added up the distributed load it would be different than the point load rating at the center.

Short of hand calculating based on the engineering data the LVLs are speced for you could play around with this software to get a ballpark idea:

When I built my house I did the calcs for my glulam beams and LVLs with that software and manually verified with hand calcs. Since I'm not a PE my local lumber yard had a PE do the beam designs for me which came out no different than what I came up with. Since I was buying the materials from them they didn't charge me to make and stamp my structural plans. Might check with your local lumber yard to see if they can help.

It might be simpler from an engineering/liability standpoint to do your LVLs apart from existing trusses?

I don't know how much point load your walls are going to take. Might need to add some posts or double+ up on studs.
 
Lifting beams/systems are generally calculated to lift a load within a certain allowable amount of deflection. Maybe something like 1:360, can't remember exact numbers, but something like that.
Glue and nail plywood to each side of your trusses, with edges touching, or sister up trusses with LVL's or whatever. Then do the calculations to find your allowable deflection; say 1:360 means 0.6" in 18 ft span.
Load up your "skyhook" and see how much it takes to get that much deflection - there's your max load.
Best make sure you have sufficient support in the walls of course.
Do some research on the span tables to get your head around the logic used. Be careful how you set your 4" steel tube in the truss to minimize the point loading.
Some of the concepts can be seen in these tables.
Bobhttp://www.ecodes.biz/ecodes_support/free_resources/Standards/AFPA/PDFs/AFPA%20-2005%20Design%20Values%20for%20Joist%20and%20Rafters%20-%20Supplement%20to%20Span%20Tables%20for%20Joist%20and%20Rafters.pdf
 
Years ago, our maintenance lads built a mezzanine in the workshop out of 2×6s and 3/4" ply. A year later the safety lady decided it needed a load-rating sign. I was selected to do the calculations. I sent the info to a friend to double-check. We both came up with about 200lbs per square yard. My boss did not believe me. The sign was never made!
 
Like said, determine your load. Build crane to accommodate. Maintain isolation between building and lifting.

I think this would be best too. Use taller lams angle cut at the end if necessary for clearance and connect them so that they straddle the truss and don't connect to it. Maybe leave the drywall open under the lam beams. You could also place a support pole under the beam only when lifting.
 
What exactly are you trying to lift? As others have said a fixed lift point isn't super useful. Are you just trying to lift a lathe chuck or a work piece? That's gonna be fine just hanging off a truss. Are you going for a couple thousand pounds? You're gonna need some more involved analysis that what you'll get from us.

What'd do though is buy a bigger laminate beam as they are cheap, put a support column at each end in the wall and throw some unistrut channel under it. Then I'd grab a cheap electric hoist from amazon and mount it on a trolley. Super cheap 'crane' option and should be fine for 500lbs without a problem.
 








 
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