Delap joined Chelsea from Ipswich for £30M last summer and just 12 months later the former Ipswich striker was placed on the transfer list after scoring just 3 goals in 49 appearances for the Blues.
The fee makes Delap the club's record signing, surpassing the £37.5m spent to bring in Omari Hutchinson from Ipswich last summer.
The forward has signed a five-year deal at the City Ground and will aim to revive his career in the midlands where Glasner says is the perfect place for him to restart.
"We were in talks for many days to be honest, we tried to convince him and obviously we could convince Liam that Nottingham Forest is the right club, at the right moment for where he is in his career.
"Also I think, before he picked Chelsea, everybody in the Premier League wanted Liam after his amazing season at Ipswich. When we heard that it was possible (to sign Delap) and we were looking for a striker, with physicality and especially pace and runs in behind. We had other profiles, with a top top striker in the box with Chris Wood, a proven Premier League goalscorer.
“We are the perfect club for him and I am convinced that he is the perfect player for us.”
Glasner continued: "As I mentioned it was the profile that convinced us and his personality when we had talks. He is hungry, he wants to improve, he wants to make a step forward and this is what we are looking for when we sign players - that they are hungry, ambitious. So the entire package looked great."
The England international had interest from several other Premier League clubs, including Everton but Forest were the side to convince him to make the switch.
Delap scored one Premier League goal in 28 appearances for Chelsea and could be handed his Forest debut tomorrow against Liverpool in front of the Anfield crowd.