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I have a 10x16 shed that use for a woodshop and am planning to remodel it soon. I currently store some lumber in the roof trusses and would like to make it a little easier to do that in the future by removing one of the ceiling joists.

Currently it is setup something like this: enter image description here

But I would like to open up the center a bit which would make it easier for me to move things into and out of the ceiling. I have come up with this: enter image description here enter image description here

So my plan is to add OSB gussets to each truss, replace the current 2x4 ceiling rafters with 2x6s, and double them up on the two inner/outer rafters to support the 2x6 box I build in the center. I think this will hold up but I'm not a structural engineer so I'm not sure if there is some issue with this I don't know about.

I would prefer not to add webbing because the plan is to maximize the amount of storage space I can get up there.

isherwood
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jesse_b
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  • I think I would prefer plywood to OSB for the gussets. The bottom rafters are more to hold the side walls together, so better solid joints(something like joist hangers) than nails will be required for the opening. – crip659 Dec 30 '21 at 13:55
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    @crip659: OSB is actually stronger than plywood for it's shear strength which is why it's more often used in structural components like that. – jesse_b Dec 30 '21 at 13:55
  • @isherwood: It's about 4' but it wouldn't make sense, if I want to put 10-12' boards up there they would only fit length wise along the shed. Also I'll have a workbench and some other cabinets along the walls so the center will be the most clear spot. – jesse_b Dec 30 '21 at 15:05
  • My understanding is that the main purpose of rafter ties is to prevent the wall from bowing out from roof load. If that's the case, would it be okay to just fasten some structure member (like a 2x10) to the bottom side of the rafter ties that are staying and to the wall top plate, kind of like a door header, but instead of supporting vertical loads, it supports the horizontal load? – Edwin Dec 31 '21 at 03:32

1 Answers1

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Some general thoughts on this, since we're lacking a few critical details...

  • You can definitely rework your rafters to eliminate the need for ties at the wall plate. Just use adequate gussets fastened adequately. See my answer on a similar question for one approach.
  • You can also just remove one tie as you propose. Almost any roof structure is stable enough to do fine with ties on 8' centers, assuming they're connected well. The gussets replace much of what the ties do.
  • You might install open racking on the walls for completely unobstructed access. This disentangles your storage from your roof framing.
isherwood
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  • How about finishing off the whole attic floor and ceiling in OSB/Ply, and gluing the flooring & ceiling to the rafters? It would make the whole attic floor/rafters/ceiling structure a torsion box, and provide more strength, perhaps? – Triplefault Dec 30 '21 at 16:47
  • It would also overload those rafter ties. You'd need more and larger. – isherwood Dec 30 '21 at 17:37