Trying to decide between building your storage shed on a concrete slab or a wood foundation can be a difficult decision. But, it doesn't have to be.
There are a couple of unique differences between slabs and wood foundations. The obvious difference of course is that a concrete slab makes the shed permanent. A wood foundation allows you to move it should you ever need to.
Either way you choose your new unit will still serve its purpose. A wood foundation (beneath the flooring) should use pressure treated lumber (aka. Osmose, Yellawood, ACQ, etc. ) which will avoid rot due to moisture. Start your foundation by laying out 2 or more skids, which could be 4x4, 6x6, or simply nail 2 2x6's together. The purpose of the skids is to keep your wood foundation off the ground so no moisture is directly on your building. It also makes your shed portable, should you ever decide to move it. Use bricks or blocks underneath the skids to level your shed floor. This also serves to keep your entire building from coming in direct contact with moisture from the ground.
The foundation should then be attached to the skids using 2x4's or 2x6's, depending on the size of the building and the amount of weight you intend to store in your shed. Lay out your 2x4's or 2x6's every 2’ measured to the center of the boards. Then you can apply your flooring. For maximum strength a 3/4" tongue and groove plywood provides a very strong foundation.
As mentioned before, building your shed on a concrete slab makes it a permanent fixture, so be sure of your location choice. Concrete slabs provide the strongest and most durable foundations capable of supporting endless amounts of weight. Be sure when attaching your walls to the slab that the bottom plate (board beneath the studs that attaches to the slab) is treated lumber. Concrete can hold some moisture so you want moisture resistant lumber used at the source. The rest of the lumber for the framework do not have to be treated.
One last point to consider in your decision is think about what you plan to store in your new storage shed. The door of a storage shed with a wood foundation, as described above, will be 8-10" or higher off the ground. This means if you plan to store heavy items such as a lawn mower, atv, etc. you will likely need to have a ramp on your shed. A concrete foundation usually would not require a ramp. If by chance it did, it could be poured at the same time as the foundation.
For more helpful information on storage sheds and the options that are available, please visit us at: