Although aged just 22, Denman has quickly built up plenty of experience of first team rugby at both Leeds Carnegie - where he came through the Academy system - and latterly at Rotherham Titans.
After playing 34 times for Leeds in the Aviva Premiership, Amlin Challenge Cup, LV= Cup, Championship and British and Irish Cup, Denman, who at 6ft tall and weighing 113kg brings a powerful physical presence to the front row, moved to Clifton Lane a year ago.
With 18 appearances for the Titans under his belt Denman is moving further down the M1 to Franklin's Gardens, where director of rugby Jim Mallinder believes he will be able to make a positive contribution to the Saints squad.
"The Championship is one of the toughest leagues to play in if you're a front row forward, and Gareth will have learned a lot very quickly over the past couple of years," he commented.
"We believe that Gareth is ready to make the step up to Aviva Premiership level, and that he has the ability to be successful at Franklin's Gardens over the next few years."
Denman himself is excited by the move to Northampton.
"It's a great opportunity and I'm glad to get back into the professional environment at a club like Northampton," he said. "I'm going to get my head down and work hard. The Championship is a tough league and my game has come along a lot just by playing, but the Premiership is another step up altogether and I've got a lot to learn.
"You look at how the likes of Brian Mujati and Tom Mercey have developed over the past few years, and I hope to follow in their footsteps, learning from the coaches and other players at Franklin's Gardens."