Laying the Slab
For most sheds, a concrete slab foundation is essential. Unless your yard is perfectly flat, you’ll need to cut and fill to provide a level surface: ideally the finished slab should be slightly raised so that water drains away from the shed.
Work with the footing plan supplied with your shed drawings, and make sure that your concreters have copies of it beforehand. Keep your slab continuously moist while it cures – the longer you can do this, the stronger it will be. Wetting it down with the hose sprinkler is a sufficient method to assist the curing of your slab. If you can do this for at least a week, it will be about 30% stronger than a fast-curing slab.