Storage sheds built on skids sometimes require leveling if the ground settles or shifts. This requires lifting the shed or jacking up the shed. The process is relatively straightforward and can be accomplished using automobile jacks and other standard tools. Jacking up a shed falls within the abilities of most do-it-yourselfers with adequate skills.
Determine the low sides or corners of the shed. Place a 4-foot carpenter's level on the floor. Raise the low end of the level until the bubble is centered. Measure the distance between the end of the level and the floor. This is the amount the sled slopes every 4 feet. Multiply this distance times the length of the shed in feet divided by 4 to estimate the amount the low end or corner of the shed will need to be jacked up.
Place a car jack under the low corner of the shed. If an entire side is low, place jacks under each corner of the shed. Excavate enough soil from under the corners so the jack will fit under the shed floor. Remove enough soil so the jack handle or crank can be operated. Place a scrap piece of lumber in the excavation to provide a flat surface for the jack.
Raise the jacks individually alternating between the two jacks. Check the level of the shed floor with the carpenter's level until you are satisfied the shed is now jacked up to the point of level.
Place shims, wedge shaped boards, between the beams of the shed and the shed floor. If the space is larger, 1- or 2-inch thick treated lumber can also be used to fill the gap. For smaller gaps, pieces of asphalt shingles can be used. Provide support for every floor joist that has been raised off the support beam during the lifting process.
Lower the jacks and refill the excavations made for the jacks.