The addition, 17 stories high, preserved the color and vertically massed profile of the original, but was more traditionally ornate in its design, with grander entranceways and more neoclassical touches. The building reflected in its design the transition taking place in skyscraper design from load-bearing walls to steel frame construction . The Katahdin, built first, used the same iron framed masonry construction as the original. The Wachusett was entirely steel framed. Where the north half required great thicknesses of brick in the load-bearing walls, the addition employed only a thin facing of brick and terracotta trim, affording larger expanses of glass and faster, less expensive construction. The south half cost 15 percent less, weighed 15 percent less, and had 15 percent more rentable space than the north half. Connected on every floor except the top one and sharing a common basement, each of the four component buildings was equipped with its own heating system, elevators, stairs, and plumbing to facilitate a separate sale if required. The combined final cost in 1893 was $2.5 million ($ in dollars).