158 West 83rd Street

 apartment building, commercial building

6-story modernist/Beaux-Arts residential/commercial building originally completed in 1911 as a 2-story post office. Known as Station W, it has more recently been occupied by a Crunch Fitness gym, which still occupies the lower two floors. They are clad in buff-colored brick. The ground floor has the entrance to the new residential upper floors on the left, with a glass door set in a recessed space with warm wooden cladding. To the right is a metal-framed commercial window, the central entrance to the gym, with glass-and-metal double-doors between windows, and at the right end is a smaller plate-glass window and a grey metal service door. The three brick piers seen at the ground floor have X-patterns in the brickwork. In the broad brick band between the two lower floors there is a wide stone panel with the lettering "STATION W NEW YORK POST OFFICE", flanked by decorative brickwork. The 2nd floor is underlined by a stone sill course and has three bays of three windows each. The end piers are paneled, and the narrow brick piers between the windows have stone caps and bases. Metal vents are cut into the two middle piers.

The 4-story addition on top was designed by SRA Architecture & Engineering and completed in 2015. It has a curtain wall of blue glass and silver stainless-steel, with a steel band separating the new section from the 2-story base. The metal mullions divide the curtain wall into five main bays. The 6th floor is set back from the building line and not visible from the street.

The building contains 22 apartment units. Much of the ground floor is occupied by Crunch Fitness.