Size and type of plywood for your shed floor. let’s take a look at what 3/4 inch pressure-treated cdx plywood is and why you want it. the 3/4 inch thick plywood is sturdy. it can support the weight of a person and heavier equipment without fatiguing over time.. The best material for the shed floor is pressure treated 3/4 inch construction grade exterior plywood. being pressure treated means wet tools or snow from the snow-blower or your boots, won’t damage the floor.. Step 4: cut and fasten plywood sheets to the frame. i used three sheets of
