Shoring up sagging shed floor
I recently purchased a rather large shed (12' X 32') and had it delivered and leveled on our rather sandy North-central Florida property. The shed floor is 5/8th in plywood over four 4 X 6's that run the long dimension of the building. Cross bracing is (i think) 2X4's.
When the delivery guy leveled he used stacked PT 2X4's at each corner and beneath the ends of the two center 4X6s, and about every 6 feet on the perimeter.
Due to time and other constraints I had most of the material I will place within it delivered and stacked in the middle of the floor shortly after the shed arrived. That material includes about 130 cartons of books plus a dozen or so hardwood bookcases.
Without bracing along the middle two 4X6s the floor is sagging pretty badly in the along middle. I've got the wiring done, but I want to get the floor leveled before I do the drywall.
Rather than trying to dig a trench to crawl through to get access to the part of the middle 4X6 members to brace them, I thought I would tear up the floor and do the bracing from the inside (after I find a place to put the books temporarily). I intend to use sold concrete pads designed for mobile homes with PT shims on top of them, and have NO wood-to-dirt contact. There is about a 10-12 inch difference in grade from front to back. I guess I'll have to dig a pit at each point I wish to brace and used a hydraulic jack to push the floor up before I put in the more permanent shoring. Any alternate suggestions or procedural heads up based on experience? Thanks in advance.
Its too bad they did such a poor job installing the shed.
Are you sure the floor joist are 4x6 I assume you meant 2x6, having 4 means they are on 2 foot centers. That is not much of a floor.
Tearing out the floor is one possibility but the plywood may be glued to the joists.
My first choice would be to call them back and have it set properly.
If that is not possible have you thought about renting some jacks, jacking the shed up to give you work space?
I think the 4x6 members would be called girders.