Expert: Bruce E. Johnson - 6/9/2011

Question
I have a shed specifically for firewood.  I have determined that the weight of the firewood when fully loaded could reach 27,600 lbs max. (6 cords) the floor area is 8' x 16' or 128 sq. ft.
If I am correct that means the flooring needs to support 216 lbs. per sq. ft.
This floor will be raised off the ground from a few inches on one and to about 2 ft. on the other end.  
I have 2 x 6 x 16 pressure treated lumber for the length ( 3 pieces, one on each side and 1 for down the middle ) and 2 x 6 x 8 pressure treated for the width ( 2 pieces, one on each end ) These will be carriage bolted to the (6) 4 x 4 vertical support beams whihc are seated in prefromed concrete footings pruchased at Lowe's whcih sit rgiht on the ground.  Then I plan on using more 2 x 6 cross bracing for more strength - all tied in using joist hangers.  Finally I plan on adding more concrete footings with 4x4 support pieces underneath to bolster up this layout.
Based upon these facts how do you recommend I build this floor?
Thank you very much for any info.  Dave

Answer
Hi dave, first of all you need to add more floor joists.  What you describe to me is 4' spacing between your joists.  For a load like this you need to space your joists more like 12" apart.  Your 16' length needs to be cut into fourths, in other words you need to add a support beam under the 16' 2x6's every four feet.  What you are building right now will sag and cave in over time..Sincerely bruce e johnson