(a) Prescriptive design/construction standards are provided for the sound insulation of new construction or modification of Group R buildings located within the most recent fourth quarter sixty-five (65) annual CNEL contour. Within the most recent fourth quarter sixty (60) CNEL to the sixty-five (65) CNEL zone, Group R buildings that are proposed for construction or modification are not required to comply with the prescriptive sound insulation standards; however, a certified acoustical engineer must provide certification that planned building modification and construction will achieve at least the forty-five (45) CNEL standard for all habitable rooms.
(b) Prescriptive design/construction standards are not provided for noise-sensitive nonresidential buildings (schools, churches and hospitals) that constitute incompatible land use within the sixty-five (65) CNEL contour; however, a certified acoustical engineer must provide certification that the planned construction or modifications will achieve the required noise environment.
(c) Deviations from the specified building requirements (i.e., standards, materials and construction assemblies) provided in the building requirements herein are permissible only if all deviations are certified to comply with and achieve the forty-five (45) CNEL standard for every habitable room constructed or modified. All deviations require approval by the Building Official and certification by a certified acoustical engineer. Acoustic measurements will be conducted by a certified acoustical engineer to verify that the forty-five (45) CNEL standard is not exceeded for all habitable rooms incorporating deviations from the building requirements.
(d) All new and modified residential construction within the sixty-five (65) CNEL contour is subject to post-construction/pre-occupancy acoustic measurement at the discretion of the Building Official. Occupation of all habitable rooms not achieving the required CNEL rating may be precluded until such time as acoustic modification of that room achieves at least the forty-five (45) CNEL standard.
(§ 2, Ord. 2616, eff. June 20, 1996)