The International Residential Code (IRC), with some state amendments, has replaced the Mass. Residential Building Code. The term used by the IRC is "sleeping space." In Massachusetts, a sleeping space is a room located in a larger dwelling space. It is used primarily for sleeping; is no less than 70 square feet in size; and has a ceiling not less than 7 ft. high. A one-room apartment with a bed and kitchen facilities is not considered to be a sleeping space.