903. BUILDING ELEMENTS AND MATERIALS

903 BUILDING ELEMENTS AND MATERIALS Insert a new Section 903.4 into the Existing Building Code to read as follows: 903.4 Air-borne sound. Walls, partitions and floor/ceiling assemblies separating dwelling units and sleeping units from each other or from public or service areas shall have a sound transmission class (STC) of not less than 50 (45 if field tested) for air-borne noise when tested in accordance with ASTM E 90. Walls, partitions and floor/ceiling assemblies separating Group A-2 occupancies from dwelling units shall have a sound transmission class (STC) of not less than 55 and shall be field tested in accordance with ASTM E 90 to achieve a rating of not less than 50 for air-borne noise. The following shall be sealed, lined, insulated or otherwise treated to maintain the required ratings: penetrations or openings in construction assemblies for piping; electrical devices; recessed cabinets; bathtubs; soffits; or heating, ventilating or exhaust ducts. This requirement shall not apply to dwelling unit and sleeping unit entrance doors; however, such doors shall be tight fitting to the frame and sill. Exception: Group A-2 occupancies that do not utilize amplified music as part of their use shall be exempt from these provisions. SOURCE: Final Rulemaking published at 67 DCR 6491 (May 29, 2020 – Part 2). The District of Columbia Existing Building Code (2017), referred to as the “Existing Building Code,” consists of the 2015 edition of the International Existing Building Code (International Existing Building Code), published by the International Code Council (ICC), as amended by the Existing Building Code Supplement of 2017 (12-J DCMR). The International Existing Building Code is copyrighted by the ICC and therefore is not republished here. However, a copy of the text may be obtained at: https://codes.iccsafe.org/public/public/collections/. District of Columbia Municipal Regulations Existing Building Code Supplement of 2017 12-J DCMR § 903