The use of hoop barns for feeding finishing pigs has expanded rapidly in Iowa. A recent survey reported over 2,000 hoops used for finishing pigs in Iowa. Extensive work on feeding pigs in hoops has been conducted by Iowa State University researchers. Finishing pigs were fed for 3 years in bedded hoop structures and a confinement building with slotted floors in central Iowa. When summer and winter feeding periods for 3 years were combined, the work showed that the finishing pigs in hoops ate more feed, grew faster, and required more feed per unit of liveweight gain than confinement pigs. Also, the hoop pigs were fatter with smaller loin muscle area and a lower percentage of carcass lean and carcass yield compared with confinement pigs. The efficiency of lean gain also was poorer for the hoop pigs.