box beam design
 

box beam design
i am building a 28' x 48' loft - metal roofing 5/12 slope, partitioned in the center making two 28' x 24' rooms. i want to span the entire 24' and support the loft floor. i would like to keep the box beam depth at 10". i was thinking 2x6 frame (like a standard wall 16"oc with doubled top and bottom plates) with 1/2 or 3/4" plywood on either side.
does anyone have experience with this type of design/construction? can you give me some idea if this is close or what would i need to carry the loft / sleeping rooms (24' x 14')?
thanks for any 'constructive' feedback.
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