This palatial room is one of the most memorable of Irish 19th-century interiors. But though its design is Victorian, its fabric is a conglomeration of the work of different periods, as is the case in most of the rooms at Iveagh House. The stairhall of today is not the one designed by Richard Castle. His design must have subdivided the present room into two, one part housing the main stairs - a single-return flight only - and the other part housing a separate service stair.
This is the arrangement of staircases seen at No. 85 St Stephen's Green. It seems clear, both from stylistic evidence and the surviving documentation, that J F Fuller completely remodelled the stairhall in 1881 and created the double-return staircase we see today. It is a splendid mahogany construction, which skilfully reuses Castle's wrought-iron balustrade interspersing the original balusters with copies. The original fretwork risers are similarly re-used and the fine carved frontispiece to the landing lintel is again 18th-century work.
On the first-floor landing are three doors designed by Fuller, the central one carved entertainingly with tropical designs - on its right-hand fold, a mahogany snake is devouring a frog. The double staircase was created at the same time as Fuller was remodelling No. 79 next door. The ceiling of the stairhall is skilfully lit by two circular skylights fitted into the narrow gap between the houses. The ceiling plasterwork mixes rococo and neo-Classical motifs in typical Fuller manner. However, the panelling of the walls, in onyx and alabaster, must be work of 1896 to William Young's designs. matching the decorative scheme of the ballroom.
The triple-arched screen leading to the ballroom, and the two rusticated arches on the half-landing, must also be due to Young. In fact the ballroom forms a much more appropriate termination to the great staircase than does the 18th-century part of the house, for both stairhall and ballroom are in a very public style They are at their most handsome at night in the artificial blaze of chandeliers.