The Redskins suffered a torrid campaign last year, winning just three matches as Griffin struggled to replicate the form from his rookie season.
Mike Shanahan, who often clashed with Griffin in 2013, has since been replaced by Jay Gruden as head coach, and the 24-year-old believes that the new coach has brought a winning attitude to the team.
"It's hard to describe but the building feels better. With the new guys we brought in, whether it's coaches or players, it's just the new attitude. It's all about winning. We're all excited about that," Griffin is quoted as saying by ESPN.
The Redskins will begin their 2014 campaign with a trip to face the Houston Texans on September 7.