There are different size tables and different length cue sticks.

The playing surface of a 9’ pool table is 50”x100”. A standard size cue stick is 57″ long. The width of the room should be large enough to accommodate the length of the cue stick on either side of the table plus the 50” of the playing surface. That totals 164” or 13’ 8”. The length of the room must accommodate the cue stick length on either side as well as the 100” of playing surface. That totals 214” or 17’ 10”.