Building an above ground pool deck can be challenging because most pools are round or oval shaped. Standard deck framing techniques do not easily accommodate this style of construction. You should know the size and shape of the pool before beginning the deck design. Most pool decks are free standing making them difficult to lay out. You don't have the advantage of a house wall to set your bearings from. You will need to install a series of footings and beams along the radius of the pool to form the shape. This will usually involve some extra labor, materials, and improvisation on the site. Your joists will hang over the beam and will terminate at the edge of the pool. Most pool decks surround one section of the pool for access and provide a space for a table and chairs. Some designs offer multiple levels including a splash deck for access to the pool. Selecting the right material is very important for pool decks. Because of the amount of water and barefoot traffic you will want to ensure the material won't deteriorate and splinter or burn feet. A composite material with a slip resistant finish is usually a good choice. A set of stairs with a self locking gate is a great idea and may be a requirement to keep unattended children away from the water.