Barr was an alpine ski racer at the beginning of his sports career and took part in races in the Nor-Am Cup . He achieved his best result on February 23, 1997 with fourth place in the Banff slalom . He was on the podium 15 times in FIS races , but never won. He contested his last alpine ski race in January 1998, after which he switched to ski cross.
Barr made his debut in the Freestyle World Cup on November 23, 2003 in Saas-Fee , where he finished 26th and won his first World Cup points. The best result in its first season was a 10th place, in the following season 2004/05 a 5th place. In addition, he won a silver medal in the UltraCross discipline at the Winter X Games 2005. Due to injury, he had to take a break for the entire winter of 2005/06, in 2007 he only took part in the World Cup.
In 2008 Barr returned to the World Cup, on February 2 of the same year he celebrated his first and so far only World Cup victory in Deer Valley . A month later, a 2nd place followed. In the 2008/09 World Cup season, a 3rd place was the best result. At the 2009 World Championships in Inawashiro he won the bronze medal, and at the 2010 Winter Olympics he finished 6th. Since then, Barr has been in the top ten in the World Cup a few times, but no podium finishes.