roof sheathing overlap

[dug]

getting ready to sheath my roof (finally! and have a question about the overlap. I have a very inconvenient sized roof (33 ft. 3 in. by 16 ft. 6 in. per side). If I use 8 ft. sheets I will only be able to overlap the sheets 2 ft. Is that O.K.? Also, I can't figure out how not to have a ton of waste, starting one course with a 3 and 1/2 ft. sheet, and ending with a 5 and 1/2 ft. sheet.

Or, I could use 10 ft. sheets and be able to overlap 4 ft. and have less waste, but it would be that much harder to haul them up to the roof.

Also- there is a dormer on one side with 5 1/2 ft. of roof left to one side of it. I assume you would not overlap this section. Is that right?

What would you do? Maybe davidj could offer some advice since they had a similar sized roof.

[davidj]

Here's the best photo I've got:

Unfortunately I think all the fiddly end stuff is hidden by the tree.  I can't remember exactly what I did, but it looks like I did overlap 2 rafter bays most of the time.  I'm guessing it went something like (in terms of rafter bays, with the end bays obviously being shorter):

  3 4 4 4 2
  2 3 4 4 4
  4 3 4 4 2
  2 3 4 4 4
  3 4 4 4 2

Note the somewhat gratuitous fiddly bit in the middle row!  Also, the loft is on the left so the structure is inherently stronger at that end, hence I did the shorter overlaps there.

As you can see, vertically I did all the fiddly stuff at the top (on the basis it was nice to carry the smallest sheets up to the higher point, and there's a fair bit of strength from the beam and rafter overlap there anyway).

[MountainDon]

First the term you want to use is stagger, not overlap.

It's sort of traditional to start a row with a half sheet but that doesn;t always work out well for materials.

The IRC states : ...roof sheathing shall be installed with joints staggered or not staggered in accordance to table R602.3(1).....   That table is the nailing schedule, for type, size and spacing of the nails.

So, staggering by one rafter bay should make a fine roof.