Any rulebook on how to start a pig farm will mention the need for a pig pen that is sturdy, spacious and has proper ventilation. Sturdy because pigs tend to become too rough, especially when you are handling them so a weak structure might get damaged easily. Pigs need enough space to move; but not too much so their muscle tissues won’t develop too much and make their meat tough. A good enclosure has around 10 by 10 feet of moving space and around 5 by 5 feet for their eating space..