Chapter 12 — INTERIOR ENVIRONMENT
Section 1206
California Building Code (Title 24, Part 2) · 2022 edition · updated 2026-09-12 · California
Italicized text is a California amendment to the model code, as printed in the official publication.
1206.1 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.
1206.2 Airborne 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 of not less than 50 where tested in accordance with ASTM E90, or have a Normalized Noise Isolation Class (NNIC) rating of not less than 45 if field tested, in accordance with ASTM E336 for airborne noise. Alternatively, the sound transmission class of walls, partitions and floor-ceiling assemblies shall be established by engineering analysis based on a comparison of walls, partitions and floorceiling assemblies having sound transmission class ratings as determined by the test procedures set forth in ASTM E90. 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 entrance doors; however, such doors shall be tight fitting to the frame and sill.
1206.2.1 Masonry. The sound transmission class of concrete masonry and clay masonry assemblies shall be calculated in accordance with TMS 302 or determined through testing in accordance with ASTM E90.
1206.3 Structure-borne sound.¶
Floor-ceiling assemblies between dwelling units and sleeping units or between a
dwelling unit or sleeping unit and a public or service area within the structure shall have an impact insulation class rating of not less than 50 where tested in accordance with ASTM E492, or have a Normalized Impact Sound Rating (NISR) of not less than 45 if field tested in accordance with ASTM E1007. Alternatively, the impact insulation class of floor-ceiling assemblies shall be established by engineering analysis based on a comparison of floor-ceiling assemblies having impact insulation class ratings as determined by the test procedures in ASTM E492.
Exception: Impact sound insulation is not required for floor-ceiling assemblies over nonhabitable rooms or spaces not designed to be occupied, such as garages, mechanical rooms or storage areas.
1206.4 Allowable interior noise levels.¶
Interior noise levels attributable to exterior sources shall not exceed 45 dB in any habitable room. The noise metric shall be either the day-night average sound level (Ldn) or the community noise equivalent level (CNEL), consistent with the noise element of the local general plan.
1206.5 Acoustical control. [BSC-CG]¶
See California Green Building Standards Code, Chapter 5, Division 5.5 for addi- tional sound transmission requirements.
Get a plain-English answer with a citation back to this text.
Ask AI about this code▸Contents — California Building Code (Title 24, Part 2)
- Chapter 2 — DEFINITIONS AND ABBREVIATIONS
- Appendix G — FLOOD-RESISTANT
- Appendix L — EARTHQUAKE RECORDING
- Appendix M — TSUNAMI-GENERATED
- Appendix N — REPLICABLE
- Appendix O — PERFORMANCE-BASED
- Chapter 1 — SCOPE AND ADMINISTRATION
- Chapter 3 — OCCUPANCY CLASSIFICATION AND USE
- Chapter 4 — SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY A…
- Chapter 5 — GENERAL BUILDING HEIGHTS AND AREAS
- Chapter 6 — TYPES OF CONSTRUCTION
- Chapter 7 — FIRE AND SMOKE PROTECTION FEATURES
- Chapter 7A — MATERIALS AND CONSTRUCTION
- Chapter 8 — INTERIOR FINISHES
- Chapter 9 — FIRE PROTECTION AND LIFE SAFETY SYSTEMS
- Chapter 10 — MEANS OF EGRESS
- Chapter 11A — HOUSING ACCESSIBILITY
- Chapter 11B — ACCESSIBILITY TO PUBLIC BUILDINGS, PUBLIC ACCOMM…
▸Chapter 12 — INTERIOR ENVIRONMENT
Overview- Section 1201
- Section 1202
- Section 1203
- Section 1204
- Section 1205
- Section 1206
- Section 1207
- Section 1208
- Section 1209
- Section 1210
- Section 1211 — [HCD 1 & HCD 2]
- Section 1212 — [HCD 1]
- Section 1213
- Section 1214
- Section 1215
- Section 1216
- Section 1217
- Section 1218
- Section 1219
- Section 1220
- Section 1221
- Section 1222
- Section 1223
- Section 1224 — [OSHPD 1]
- Section 1225 — [OSHPD 2]
- Section 1226 — [OSHPD 3]
- Section 1227 — [OSHPD 4]
- Section 1228 — [OSHPD 5]
- Section 1229
- Section 1230 — [BSCC]
- Section 1231 — [BSCC]
- Section 1232
- Section 1233
- Section 1234
- Section 1235 — [DPH]
- Section 1236 — [DPH]
- Section 1237 — [DPH]
- Section 1238
- Section 1239
- Section 1240 — [AGR]
- Section 1241 — [AGR]
- Section 1242 — [AGR]
- Section 1243 — [AGR]
- Section 1244
- Section 1245
- Section 1246
- Section 1247
- Section 1248
- Section 1249
- Section 1250 — [CA]
- Section 1251 — [CA]
- Section 1252 — [CA]
- Section 1253 — [CA]
- Section 1254 — [CA]
- Chapter 14 — EXTERIOR WALLS
- Chapter 15 — ROOF ASSEMBLIES AND ROOFTOP STRUCTURES
- Chapter 16 — STRUCTURAL DESIGN
- Chapter 16A — STRUCTURAL DESIGN
- Chapter 17 — SPECIAL INSPECTIONS AND TESTS
- Chapter 18 — SOILS AND FOUNDATIONS
- Chapter 19 — CONCRETE
- Chapter 20 — ALUMINUM
- Chapter 21 — MASONRY
- Chapter 22 — STEEL
- Chapter 23 — WOOD
- Chapter 24 — GLASS AND GLAZING
- Chapter 25 — GYPSUM BOARD, GYPSUM PANEL PRODUCTS AND PLASTER
- Chapter 26 — PLASTIC
- Chapter 27 — ELECTRICAL
- Chapter 28 — MECHANICAL SYSTEMS
- Chapter 30 — ELEVATORS AND CONVEYING SYSTEMS
- Chapter 31 — SPECIAL CONSTRUCTION
- Chapter 31B — PUBLIC POOLS
- Chapter 31C — RADIATION
- Chapter 31D — FOOD ESTABLISHMENTS
- Chapter 31F — MARINE OIL TERMINALS
- Chapter 32 — ENCROACHMENTS INTO THE PUBLIC RIGHT-OF-WAY
- Chapter 33 — SAFEGUARDS DURING CONSTRUCTION
- Chapter 35 — REFERENCED STANDARDS
- Appendix A — EMPLOYEE QUALIFICATIONS
- Appendix B — BOARD OF APPEALS
- Appendix C — GROUP U – AGRICULTURAL BUILDINGS
- Appendix D — FIRE DISTRICTS
- Appendix F — RODENTPROOFING
- Appendix H — SIGNS
- Appendix I — PATIO COVERS
- Appendix J — GRADING
- Appendix K — GROUP R-3 AND GROUP R-3.1 OCCUPANCIES
- Appendix P — EMERGENCY HOUSING