Taking place over the summer, the investment, included changes to the reception, gallery, Lakeview restaurants, lounge and bar.
These areas have received new floor and wall coverings, decoration, flooring, windows, furniture and refreshment facilities. Six syndicate rooms have also been upgraded with AV equipment and low-energy lighting has been introduced.
Alan Robinson, Warwick Conferences' director of training and conference centres, said: "The works completed to Scarman over the summer are indicative of our ongoing commitment to providing delegates with modern, clean, efficient and purposeful facilities. The upgrades completed not only ensure this objective continues to be met and even exceeded but will also introduce efficiencies made possible by modern technologies.
"With Scarman celebrating its 20th anniversary this year, the investment is a fitting birthday present to a hardworking and respected venue."
The investment forms part of a multimillion pound refurbishment programme.
Works already completed across Warwick Conferences include the refurbishment of the bedrooms at Scarman, dining facilities at Arden and upgrades throughout Radcliffe.