Boardman was born in Mortimer Common, Berkshire and joined Crystal Palace as a trainee in June 1999, turning professional on 7 July 2000. On 22 March 2001, he joined Woking on loan to gain some first-team experience in the Conference, returning to Palace at the end of the season.
On 23 August 2001, Boardman accompanied his Palace team-mate David Woozley to Torquay United and began a week's trial (whilst Woozley was signed on a month's loan). However, he returned to Selhurst Park without being registered to play for the Gulls. It later transpired that Palace had thought he was joining Torquay on loan, whereas Torquay manager Roy McFarland had simply wanted to see him in training. In October 2001, he joined Conference side Margate on loan.
Later that season he joined Woking on loan, moving to Woking on a free transfer in March 2002 after his release by Crystal Palace, having spent the three previous months on loan at Woking. He had not played a single first team game for Palace. He remained with Woking until May 2005 when he joined Rochdale.
He was a regular in his first season with Rochdale, but became a fringe player and had his contract cancelled by mutual consent on 22 January 2007. A week later he signed for Conference National side Dagenham & Redbridge.
In June 2009, Boardman rejoined Woking.
In June 2010, Boardman joined Ryman League side Kingstonian to help with their 2010-2011 campaign to get into the Blue Square South.
After relocating back to Reading Boardman decided to cancel his contract with Kingstonian and has now signed for Hungerford Town in the Southern League Division one South & West.
Boardman currently writes a monthly column for UK football magazine Shoot Monthly.