The Cavendish Hotel near Chatsworth Estate has been granted planning permission to turn its on-site single tenancy coach house into four new bedrooms.
The four-star hotel currently has 23 bedrooms and the expansion will include a ground floor room with access for wheelchair users.
The Duchess of Devonshire will oversee the interior design of the new rooms and has worked with architects Haxton Koyander of Chesterfield and interior designer Rachel Maclane.
The Duchess said: “I have worked with Rachel on previous projects and look forward to creating a luxurious yet practical addition to the hotel.
“The rooms will be all about creature comforts with a striking style whilst being sympathetic to the fabric of the building. From power points to power showers, our attention to detail will ensure guests will want for nothing.”
The coach house conversion will be made available for the exclusive use of small groups, and visitors will share the same facilities as those in the main house of the hotel.
Philip Joseph, managing director, said: “The coach house is adjacent to the hotel’s Grade II listed building and as such it is important we maintain its integrity and safeguard the historical importance.”
The expansion is expected to be completed in the autumn.