Chapter 12 — INTERIOR ENVIRONMENT
Section 1204
California Building Code (Title 24, Part 2) · 2019 edition · updated 2026-09-12 · California
Italicized text is a California amendment to the model code, as printed in the official publication.
1204.1 General.¶
Every space intended for human occupancy shall be provided with natural light by means of exterior glazed openings in accordance with Section 1204.2 or shall be provided with artificial light in accordance with Section 1204.3. Exterior glazed openings shall open directly onto a public way or onto a yard or court in accordance with Section 1205.
[HCD 1] Glazed openings may open into a passive solar energy collector provided the area of exterior glazed open- ings in the passive solar energy collector is increased to com- pensate for the area required by the interior space.
1204.2 Natural light.¶
The minimum net glazed area shall be not less than 8 percent of the floor area of the room served.
1204.2.1 Adjoining spaces. For the purpose of natural lighting, any room is permitted to be considered as a portion of an adjoining room where one-half of the area of the common wall is open and unobstructed and provides an opening of not less than one-tenth of the floor area of the interior room or 25 square feet (2.32 m 2 ), whichever is greater.
Exception: Openings required for natural light shall be permitted to open into a sunroom with thermal isolation
or a patio cover where the common wall provides a glazed area of not less than one-tenth of the floor area of the interior room or 20 square feet (1.86 m 2 ), whichever is greater.
1204.2.2 Exterior openings. Exterior openings required by Section 1204.2 for natural light shall open directly onto a public way, yard or court, as set forth in Section 1205.
Exceptions:
- Required exterior openings are permitted to open into a roofed porch where the porch meets all of the following criteria:
1.1. Abuts a public way, yard or court.
1.2. Has a ceiling height of not less than 7 feet (2134 mm).
1.3. Has a longer side at least 65 percent open and unobstructed.
- Skylights are not required to open directly onto a public way, yard or court.
1204.3 Artificial light.¶
Artificial light shall be provided that is adequate to provide an average illumination of 10 footcandles (107 lux) over the area of the room at a height of 30 inches (762 mm) above the floor level.
1204.4 Stairway illumination.¶
Stairways within dwelling units and exterior stairways serving a dwelling unit shall have an illumination level on tread runs of not less than 1 footcandle (11 lux). Stairways in other occupancies shall be governed by Chapter 10.
1204.4.1 Controls. The control for activation of the required stairway lighting shall be in accordance with the California Electrical Code.
1204.5 Emergency egress lighting.¶
The means of egress shall be illuminated in accordance with Section 1008.1.
1204.6 Light pollution reduction. [BSC-CG]¶
See California Green Building Standards Code, Chapter 5, Division 5.1 for additional light pollution reduction requirements.
1204.7 Campus lighting for parking facilities and primary¶
walkways at california state universities, colleges and com- munity colleges. [BSC] Artificial light shall be provided for parking facilities and primary walkways at California State Universities, colleges and community colleges in accordance with provisions of this subsection. This subsection shall not apply to the University of California unless the Regents of the University of California, by resolution, make it applicable.
1205.7.1 Lighting requirements. Based on the recommen- dations of the most current edition of the Illumination Engineering Society lighting handbook, the following lighting standards shall be used for all new construction of open parking facilities, covered parking facilities and primary walkways:
1. Open and covered parking facilities.
1.1. Medium-level activity usage when medium usage is present. 1.2. High-level activity usage when high usage is present. 2. Primary campus walkways.
650 2019 CALIFORNIA BUILDING CODE
Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.
100735044
2.1. Medium-level activity usage when medium usage is present.
2.2. High-level activity usage when high usage is present.
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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
- Chapter 1 — SCOPE AND ADMINISTRATION
- Chapter 3 — OCCUPANCY CLASSIFICATION AND USE
- Chapter 4 — SPECIAL DETAILED REQUIREMENTS BASED
- 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 1211 — [HCD 1]
- Section 1210 — [HCD 1 & HCD 2]
- Section 1212
- 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 & OSHPD 1R]
- 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 N — REPLICABLE BUILDINGS
- Appendix O — EMERGENCY HOUSING