Basically, you need a copy of your property plat that shows the house and its location along with the property lines. Specify where the new deck will go on the plat. There's also a county fee and an application for a permit. You'll also need a drawing of the deck to scale (usually to 1 inch equals 1 foot) that shows the dimensions, footer size, beam size, joist size, decking material, railing system and staircase location if any. To expedite the permit process, you'll need your county property tax account number. Whenever you're designing your deck, make sure you stay within any setback requirements and building restrictions, which should be clearly marked on your property plat.