According to the Swimming Pool Ideas website, pool decks should be at least 4 feet wide. Pool decks that are at least 4 feet wide provide a safe surface for entering or exiting the pool. Municipal codes for residential pool deck generally require 4 foot wide decks.
The only physical limitation on an in-ground pool deck is the size of the yard. Municipal zoning may impact how large your pool and its deck can be. Also, the various proportions of a pool and deck should be taken into consideration.
If you want an in-ground pool, you need to make sure your yard is big enough. To figure the size of a pool plus its deck, add 8 feet each to a pool's width and its length. For example, if your pool will be 18 feet wide by 40 feet long you'll need a yard at least 26 feet wide by 48 feet long. Swimming pool footprints are also known as their "base wides."
Pool decks aren't normally included in the base costs of in-ground swimming pools. Pool decks can be made of concrete, pavers, wood, or other materials. Some municipalities classify decks wider than 4 feet as patio decks, which require different building permits. Nearly all municipalities require permits for installation of a pool and deck.