OSB ceiling layout

[nfk]

I'm looking for opinions on laying out the OSB for my garage ceiling. The garage is 30x40 with hip roof trusses. The full trusses run east-west and the hip trusses run north-south.
I am planning on running my 4x8 OSB sheets north-south to tie the main trusses together. Trusses are on 2' centers. Although the first hip truss is not 2' oc from the exterior wall.

My debate is if I want to rip the entire first row (5 sheets) of OSB so that the edge of the osb falls on the center of the hip trusses.(width of sheets won't matter once I'm too the full trusses)
My other option is to start with a full sheet (which will fall between the hips) and put blocking on 2' centers between the hip trusses where the edge of the sheet will fall. By doing this I will have to place blocking between the hip trusses on every row of osb. Approx. 40 blocks.
My third option is to run full sheets and screw strips of OSB to the top sheet edges between the hips tying the adjoining sheets together.
What do you guys think? How is this done when drywalling a ceiling?

Hopefully this makes sense and isn't too confusing. Thanks.

 

[Chris705]

I think when hanging drywall it makes sense to cut the board to make sure the **** joints land on solid framing. The joint compound is going to hide everything. With your OSB I think you'll be happiest if all the joints line up perfectly. So I say go for your last thought & use strips along the hip truss ceiling panels that don't line up.

 

[dfiler2]

If a person were using drywall you would want to put the bocking in but I think I would do the blocking using OSB also.

 

[gregtwojeeps]

Yep, blocking is best. OSB will sag if spanned too far. Putting a strip of OSB on top of the osb at the joints just combines the weight at the end of the two sheets making the joint weight heavier = making the potential to sag even worse. jmo

 

[nfk]

So it seems the general consensus is to start with a full sheet and use blocking between every sheet on the hip trusses vs. ripping the first row down to 33" wide to fall on the center of a hip truss.
I was originally planning on going this way but after I realized how much blocking I would need (approx 60' of 2x4s) I thought about ripping the first row down to save some work and materials in the blocking. Although I would then have the work of ripping the sheets down. Not to mention having to rip down the row of sheets when I get done at the other side of the building.
Im seeing this as one of the drawbacks to a hip roof....
Thanks for the replies.

 

[kbs2244]

You need the blocking.
It will stiffen the joint a lot.
And "brick lay" the panels so you do not ahve any four meeting at one place.
That stiffens things also.

 

[nfk]

I've been preoccupied, bit I finally got started on the ceiling.