Very space conscious.  Not sure it really matters that it is not 4' wide but since a full width piece will stick out anyway, you might as well make it 4'.  

My only concern is that moving a full sheet in the vertical orientation may be a lot harder than horizontally.  It is awkward enough sideways.  

--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.