The Red and Green Regency Rooms are in the south wing on the ground floor.
They were decorated in the Regency period around 1820 with thick walls dating from the 1400s. This wing is the earliest part of the house and originally formed the full extent of the building.
In the courtyard wall there are the remains of two spiral staircases; the thickness of the 15th Century walls can be judged from the window openings. In the 1760s John Carr of York altered the wing to form three reception rooms in the neo-classical style.
In 1812 Peregrine Towneley commissioned the architect, Jeffry Wyatt, to remodel and modernise the house. Wyatt created these two rooms with their round-headed windows.
The first room, used as a dining room, had both the green marble fireplace and a system of underfloor heating fitted. The second room contains the fireplace originally supply by the sculptor, Richard Hayward, in 1780. The central heating was added by Burnley Corporation in 1903.
These rooms, designed for entertaining, would be hung with two rows of paintings, and also acted as art galleries, the furniture being arranged around the walls.
Today the first room is used as a temporary exhibition room whilst the Red Regency Room is used for concerts, weddings and other special events. The Red Room has been painted in the original colour scheme and is furnished in period. Three of the chairs are from the Northumberland House suite made by Morel and Hughes in aburra wood in 1823 for the Duke of Northumberland.