The first phase of the development will upgrade four of the hotel's conference rooms, with a further four new breakout rooms being built on the top floor of the main building.
The breakout rooms will include two executive boardrooms and a 'creative hub', which will be free for delegates to use alongside the meeting rooms. There are 26 meeting rooms in total.
Anna Snoep, director of sales and marketing at Down Hall Country House Hotel, said: "Our focus is on innovation and giving our clients more choice, with healthy food that is both delicious and nutritious and all the support they need to make their meetings and events successful."
The first phase of the refurbishment is set to be completed by Spring 2014 with the second phase expected to begin later this year.