A storage shed can be a fixture in your backyard for 20 years or more if it is installed correctly. The key to a durable storage shed is the foundation upon which it rests. To give your storage shed the long life it deserves, make sure to lay the right foundation. Crushed stone is a relatively inexpensive option and provides a solid base for a storage shed foundation.
Mark off the area of your yard where the storage shed will be placed with a chalk line or string. Make the dimensions 2 inches longer and wider than the shed so the crushed stone base will extend beyond the drip line.
Remove approximately 4 inches of the grass and dirt for the base of the storage shed. When you are finished, there should only be dirt inside the area where the storage shed will rest.
Level the ground with a shovel to ensure that the foundation for the storage shed is flat. Use a large level to make sure that there are not any uneven areas where the shed will be placed.
Pour crushed stone over the prepared area for the base of the storage shed. The crushed stone should be no larger than a half-inch in diameter and should be even with the ground when finished.
Compact the crushed stone base with a hand tamper or a metal roller to ensure that it is compacted and level.
Pour a 1-inch thick base of dry sand over the crushed stone base. Run the flat side of a metal rake over the sand to work it into the crushed stone.
Lay paving slabs down over the crushed stone base and use a level to make sure that they are even. Tap any uneven slabs down with a rubber mallet.
Try to choose a storage shed site that is as level as possible and does not have much slope. This will make the site preparation much easier. If you do not add 2 inches on each side of the storage shed's measurements for the drip line, it will cause dirt and debris to be splashed onto the sides of the shed when it rains.