Unlike most eighteenth century houses of similar stature, Gunston Hall’s second floor does not mimic the four part layout of the floor below. Instead, it features seven bedchambers and a storage room connected by a narrow passage running the length of the house. The floor's most distinguishing architectural feature is an elegant tri-part arch with fluted pillars at the top of the main stairs; this served to visually separate the corridor from a small gallery overlooking the staircase. Access to the second floor was also provided by a narrow staircase used by slaves and servants and located across from the storage room.
Amongst the bedchambers, the four corner rooms had the best accommodations. Their fireplaces and surrounds had some architectural detailing and they had more windows. Interior chambers have only one window and no fireplace, making these far less desirable spaces. Access to the attic is provided through one of the center chambers; it is possible that some of the slaves or servants slept in that attic space.
The eighth space on the second floor is a storage closet, or as it was sometimes called at that time a lumber room. With no exterior window, the lumber room depends on an unusual interior window for its light. This “robber” window faces into the stairwell, gleaning or robbing its illumination from the exterior window above the staircase landing.