A floor assembly for a performance space is disclosed. The assembly has a planar resilient floor board supported above a base board on a primary support system comprising a plurality of resilient (preferably elastomeric) supports. A secondary support system comprises a plurality of fixed support members and a plurality of movable support members. Each movable support member is movable in a direction parallel to the plane of the floor board between a first position spaced from a corresponding fixed support member such that the floor board is unsupported by the support members and a second position in contact with the corresponding fixed support member such that the floor board is supported by the support members. In the first position, the floor board is in a sprung configuration and in the second position, the floor board is in an unsprung configuration. The invention therefore provides a performance floor which is switchable between sprung and unsprung configurations.