The estate's Georgian-era owners, the Beaumonts, commissioned the Camellia House in 1812 to house collections of exotic plants imported from Asia, as was the fashion among British gentry at the time.
The building later fell into disuse after the Beaumonts sold their seat near Wakefield to West Riding County Council in 1947 and the site became a teacher training college.
Despite the estate being used for educational purposes until 2007, the camellias themselves - known to be hardy specimens - have survived inside the building, which was designed by Jeffrey Wyatt, a leading architect of the day who also worked on Chatsworth and Windsor Castle. Its glazed roof remains intact.
It is one of several remaining listed heritage structures within the hall's parkland, which is now home to the Yorkshire Sculpture Park.
Leeds-based property developers Rushbond and hospitality company Artfarm have entered into a partership to renovate the Camellia House to complement Rushbond's conversion of Bretton Hall into a hotel complex.
The camellias themselves will be protected during the work and remain in situ.
The project echoes work that has taken place on the Wentworth Woodhouse estate near Rotherham, where a listed Camellia House from the same period will also be restored and opened as a cafe and events venue with the rare plants still inside.
Rushbond director Mark Finch said: “The renovation of the Camellia House is a key chapter in the unfolding story of Bretton Hall. The work plays a vital part of our wider plans to transform
Bretton Hall and its estate as a cultural destination that complements the amazing Yorkshire Sculpture Park and helps promote the Wakefield as a creative and cultural hub.”
Conservation architect Lisa McFarlane added: “The Camellia House plays a hugely important role in telling the wonderful story of Bretton Hall and its former life as a country house. It’s a building that is close to the hearts of many visitors who come to admire the beautiful collection of camellias, as well as the magnificent sculptures that have been displayed alongside
them over the years.
"The restoration of the Camellia House marks an important milestone in the ongoing transformation of the estate to ensure its long-term protection for the enjoyment of visitors
from all over the world.”