Half width plywood subfloor?

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Aug 19, 2010
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I am wanting to put a subfloor in an attic space with very limited hatch access. There's no easy way to get 4x8 pieces up there - is it possible to use 2x8 pieces? Are there any changes to how you would do this, or is it a no-go? Thanks!
I did a ceiling in the basement of my old house using what they call pegboard garage paneling. No way could I get 4x8 down there so I cut them into three 16” and then staggered the joints.

No reason you can’t rip the sheets for your floor. Most lumber yards have a panel saw and will give you one cut for free. So I would let them do the work and make it easier to haul as well. Just make sure the kid doing it knows what he’s doing and splits them right down the middle.
Lay a sheet of ply with a block on each 8' side, now step in the middle of the sheet, or on thin ply, see it bow.

If you are splitting it lengthwise then use plywood clips at the joint.
I’m assuming with hatch access you are not planning on using the space as a room but rather a place to stick some Christmas decorations or luggage that is seldom used. Be aware roof spaces (attic) are not designed to take floor loading most of the time like a bonus room that may have been left unfinished. It wouldn’t be the place to store many boxes of books say.

Knowing your intended usage of the space and how much of the space you want to floor off would determine what would be best. Light seasonal stuff being stored I would rip .5” OSB and screw it down and I think you would be ok.

Also keep in mind the space will get cold in the winter and hot in the summer.