D.C. Mun. Regs. tit. 12, r. 12-A1207
Strike Sections 1207.1 and 1207.2 of the International Building Code in their entirety and insert new Sections 1207.1 and 1207.2 in the Building Code in their place to read as follows:
Scope. This section shall apply to common interior walls, partitions and floor/ceiling assemblies between adjacent dwelling units and sleeping units or between dwelling units and sleeping units and adjacent public areas such as halls, corridors, stairs, service areas, or Group A- 2 occupancies.
Interior 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 and sleeping units shall have an STC of not less than 55 and shall be field tested to achieve a rating of not less than 50 for air-borne noise. Penetrations or openings in construction assemblies for piping; electrical devices; recessed cabinets; bathtubs; soffits; or heating, ventilating or exhaust ducts shall be sealed, lined, insulated or otherwise treated to maintain the required ratings. 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.
Exceptions: Group A- 2 occupancies that do not utilize amplified music as part of their use shall be exempt from these provisions.
D.C. Mun. Regs. tit. 12, r. 12-A1207