The Singer Building contained a vacuum steam system, although the ground floor lobby and the basement vaults were heated by an indirect-steam system. Heating came from steel radiators on each floor; the radiators in the ground-floor banking rooms and the Singer Company's 33rd and 34th floor offices were enclosed within ornamental screens. About 1,600 steam radiators were installed throughout the building. In addition to providing heat, the building's boilers also provided power to the entire building. The boilers had to generate of steam pressure to meet demand. Initially, the Bourne and original Singer buildings had boilers aggregating and power generators with a capacity of . With the 1906-1908 addition, boilers aggregating were installed, and generators with a capacity of were added, replacing the old ones. A steel smokestack at the northwest corner of the building was shared with the City Investing Building to the north.