Once you have all your joists cut mock up the frame by placing the joists inside the frame.
Best to run shed floor joists lengthwise or sideways.
All cuts should be painted with a wood preservative to prevent rot.
Mark the 12 inch increments along the length of the frame.
You might need a helper if you want to go bigger than this.
You want your joists to sit 12 inches on center.
Also cut your 4 x 4 skids to length.
With a proper moisture barrier this can be the best floor you could build.
Skids usually run the length of the shed and are the same length as the floor.
Then cover with plywood.
The hole and angled cut at both ends means the shed can be pulled from either end.
While you may be ok with the joist span at 24 inches the floor will be maxed out to the limits.
Nail horizontal floor joists and plywood sheets on top.
Some people will tell you 16 inches is ok but i like to make my shed floor extra strong.
Cut all floor joists to proper length along with your 2 rim joists and two band boards and skids.
This is one of the best ways to stop a shed floor rotting.
If the choices are plywood or osb for your shed floor the plywood wins every time.
After cutting all lumber mark off your two band boards for joist layout at 12 on center.
Build the walls and rafters out of wood beams and make sure to build the back wall slightly shorter to create a slant.
Clean out the holes the holes should line up with what you plan to connect to on the shed.
Use a hammer drill with a concrete bit to make the holes for the concrete expansion bolts.
Joists are sometimes used to create a level deck to support bearers for a shop bought shed.
Usually anything under 10 x12 or so can be done by a single person.
The joist next to the rim joist is best but the rim joist will work if you cannot reach the other.
It won t cost you much more in the long run.
Gather the proper lumber to cut your floor joists rim joists and 2 two band boards and 4x4 skids.
Spacing joists in your shed 16 inches on center will give you a firmer feel with less bounce and increase the load capacity of the floor.