Ideal flooring options for sheds involve a type of floor that is mobile in case the shed needs to be relocated. But it still needs to be stable and sturdy. A wood floor using treated lumber and plywood offers the stability without the permanence of cement slabs. Building a 10-foot by 10-foot wood floor for a storage shed requires building a frame similar to the joists and studs used in housing. The flooring rests directly on top of cement blocks to elevate the shed off of the ground slightly.
Measure and cut two 2-inch by 6-inch beams to 10-feet long with a circular saw. Cut eight 2-inch by 6-inch beams to 9-feet and 9-inches in length.
Assemble the basic frame with the 10-foot beams running horizontally and the 9-foot 9-inch beams running vertically between the two 10-foot beams.
Attach the first and last 9-foot 9-inch beams so that the edges of the beams are flush with the ends of the 10-foot beams and the 6-inch sides stand straight up for all the beams. Drive two 3-inch, self-tapping, exterior grade wood screws through the exterior edge of the 10-foot beams into the ends of the shorter beams with a drill and screwdriver drill bit, creating a basic box.
Make a vertical line mark every 16 inches from one end of the box on each of the 10-foot beams, creating pairs of marks. The result will be 7 pairs of marks with the last pair sitting 8-inches from the end.
Attach the 9-foot 9-inch beams to the pairs of marks with two 3-inch screws drilled into each end to complete the frame.
Lay out sheets of plywood so that the ends of the plywood sit on top of vertical beams. Eight-foot sheets will be the best fit working from one side. Cut additional sheets with a circular saw to 2-feet to fit the remaining exposed section.
Attach the plywood sheets to the frame with 3-inch screws spaced 8 inches along each vertical and horizontal beam.