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I'd like to make or build a block-and-tackle in my garage to be able to lift up to a thousand-pound load (e.g. a moose). I think I have a handle on the design of a block-and-tackle and the selection of rope, etc., but what I'm struggling with is how to attach it to my ceiling joist(s).

The joists are 2x8s and they are exposed so I can get up there if I need to drill holes, bolt through them, etc. I'm not sure how far apart they are but I think it's about 2 feet. The simplest approach would be a single eye bolt screwed into one joist, but I don't know the weight ratings for eye bolts and I'd be worried that the wood might fail (I don't know the species) or the bolt might unscrew over time. So I've been thinking instead about perhaps running a steel bar horizontally between two or more joists and hanging my block-and-tackle from that bar. Or maybe a wooden beam, but how would I fasten that to reliably hold the weight? Another possibility might be multiple eye bolts in one or more joists and a small web of ropes coming together to lift the block.

TLDR: what is a safe and reliable way to attach a block and tackle with a 1000-lb weight to a ceiling with exposed 2x8 joists?

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    What is the span of the 2x8’s? – Lee Sam Apr 22 at 3:53
  • does that mean how long they are? I think about 16 feet. spaced about 24" apart. – Joe Apr 23 at 1:41
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You want a LONG beam on TOP of the joists to spread the load over LOTS of joists, since your garage is probably not designed to have very much (if any) load on those (particularly if there is not a floor on top of them, which it sounds like.) I'd suggest 10 or 12 feet minimum so you pick up 5 or 6 joists to share the load. 16 feet would be better.

You can throw some hurricane ties at it to hold it in place. It wants to be "on edge" (if it's not square, the narrow sides should be top and bottom, since the depth of a beam is where its strength is.) If it's square, you don't really NEED to hold it in place, as it won't roll over, and gravity will hold it there just fine.

A section of chain around the beam is a good way to hold a block without depending on a bolt attachment. Lift-rated eye bolts are available, but they are fairly costly. Chain and chain accessories rated for 3000 or more pounds are easy to come by. But make sure every element is rated for (several times) the load you want to carry. Do NOT use "1000 lb rated" parts if you actually want to lift 1000 lbs - always add a safety factor.

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    But to be clear, a safety factor isn't like "an extra 50 pounds". A safety factor is like "4 times". Especially if you're buying from Harbor Freight / Canadian Tire / China. – Harper Apr 22 at 11:14
  • It was my understanding that "working load" ratings already have a 3x safety margin. For instance, a HD tie down strap may have a strength of 10,000lbs, but sold with a "working load" of 3000. – JPhi1618 Apr 22 at 13:24
  • i have an upper floor on top of the joists, so getting on top of them isn't possible for this project – Joe Apr 22 at 17:52
  • Sure it is possible - put the beam on the floor, drill two holes or one hole depending on if you are using a chain around the beam or a bolt through it to hold the block. You may not want to, but it's very possible, and those are different things. Both the previously requested span of the 2x8's and how much stuff (that's how heavy) you are storing on that floor come into play, of course. – Ecnerwal Apr 22 at 17:58
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A 2x8 spanning 16’ will support about 60 lbs. per foot, (depending on species and grade). So, 2x8’s at 24” on center will support about 30 lbs. per square foot.

The building Code requires a floor support a minimum of 30 lbs. per square foot Live Load plus all Dead Loads. (Dead loads are carpet, sub flooring, joists, etc., which is usually about 10 lbs. per square foot.)

So, it appears your joists are currently slightly overloaded, (30 psf + 10 psf = 40 psf). Adding a 1,000 lbs. load could be detrimental.

BTW, you may want to double check the span. You guessed at 16’. (At 15’ the allowable load goes up from 60 plf to 70 plf. )

I’d add a 4x8 in lieu of connecting to the existing structural system.

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