Career
Lahousse started his career with Roeselare in the Belgian Second Division, playing his first match during the 2001-2002 season. Lahousse was a key player in the Roeselare team that became third in 2003-2004 and narrowly missed out on promotion during the playoffs. He remained a key player after the promotion, playing 34 matches and scoring two goals in the 2005-2006 Belgian First Division.
He only featured seldom in the following season, causing him to leave Roeselare in June 2007, when he signed for second division team Ohio Leuven.
Again he became a key player, playing 56 matches in two seasons before moving to Oostende in the same division, where he played 55 matches in two seasons before moving to Boezinge at the fifth level of Belgian football.