During the addition of the north wing between 1745 and 1765, the main entrance to the Manor Hall was reoriented to face the Albany Post Road. The new stair hall and foyer contained a U-shaped staircase that is the dominant feature of the space. The staircase features an open stringer design, with stained wood treads, risers, decorative floral carvings, and a wide mahogany balustrade. J. Ritchie Garrison notes:
“Grand, open string staircases with elaborately turned balusters and prominent newel posts appeared in court-level architecture in England in the last quarter of the seventeenth century, and showed up in the builders’ guides published in the 1730s and 40s. The large volute on the example at Philipse Manor Hall is consistent with the pattern shown in plate 32 of Abraham Swan’s Palladio Londonensis published in 1738…”
Mahogany, the wood used for the balustrade, or handrail, was the most sought after imported wood used in the eighteenth century. Native to Jamaica, the luxury product used for furniture, objets d’art, and architecture created a high demand that almost wiped out the species by 1748. The desire for it extended not just to the elite class, but to anyone who could afford it. According to Jennifer L. Anderson,
“although its initial introduction and popularization were similar to that of other tropical commodities [sugar, tobacco, chocolate, etc.], its long-term history followed a very different trajectory because of three key factors: its limited availability, its durability and its increasing scarcity…”
The mahogany’s highly polished sheen on the elaborately decorated staircase would have impressed anyone visiting the Manor Hall upon entering and seeing it, and left no doubt about the family’s wealth and status.
 Garrison, J. Ritchie, Philipse Manor Hall: An Historical Context and Stylistic Analysis, New York State Office of Parks, Recreation and Historic Preservation, 2005, p.32
 Anderson, Jennifer L., Mahogany: The Cost of Luxury in Early America, Cambridge, Harvard University Press, 2012, p. 7.