CRC · California Residential Code

What are the minimum room area and ceiling‑height rules?

Summary: For most California homes the CRC requires habitable rooms to be at least 70 sq ft (kitchens excepted) and at least 7 ft in a horizontal dimension; habitable spaces must generally have a **7 ft** ceiling while bathrooms and some basement/attic situations allow reduced heights (e.g., **6 ft 8 in**). Portions of rooms below specified low heights (notably **5 ft** under sloped ceilings) do not count toward the minimum area — see **§ R312** and **§ R313** for the exact rules.

Ask a question free See coverage

Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

In plain English: every habitable room (except kitchens) must be at least 70 square feet and at least 7 feet in any horizontal dimension, and habitable spaces generally must have a ceiling height of at least 7 feet. Bathrooms, toilet rooms and laundry rooms have reduced ceiling‑height minimums (6 feet 8 inches) and there are specific rules for sloped ceilings, furred ceilings, mezzanines and basements. These requirements are set out in § R312 (minimum room areas) and § R313 (ceiling height) of the California Residential Code.

The single most important rule: a habitable room (not a kitchen) must give you at least 70 sq ft of usable floor area, and the usable area must meet the ceiling‑height rules (portions below the minimum heights don’t count). § R312.1 / § R313.1

Requirements in detail

Key defined terms (first mention)

  • Habitable room — a room intended for living, sleeping, eating or cooking (note: kitchens are explicitly excepted from the 70 sq ft min in § R312.1). § R312.1
  • Sloped ceiling — any ceiling that slopes (special area/counting rules apply). § R313 (exceptions)
  • Furred ceiling — a dropped/soffited ceiling; area-counting rules differ from full-height ceilings. § R312.3 / § R313.1.1

Decision‑relevant dimensions and values

Requirement Value (imperial / metric) Where to use it Code Reference
Minimum floor area for a habitable room (except kitchens) 70 sq ft (6.5 m²) Any habitable room (bedroom, living room, etc.) § R312.1
Minimum horizontal dimension for habitable rooms 7 ft (2134 mm) Any plan dimension of a habitable room § R312.2
Portions of room not counted toward area (sloped/furred) Less than 5 ft (1524 mm) for sloped ceilings; less than 7 ft (2134 mm) for furred ceilings Those portions are excluded from required habitable area calculations § R312.3
General minimum ceiling height (habitable space & hallways) 7 ft (2134 mm) New construction habitable spaces and hallways § R313.1
Bathrooms, toilet rooms, laundry rooms ceiling height 6 ft 8 in (2032 mm) Bathrooms, toilets, laundry in new construction § R313.1
Sloped ceiling exception (required floor area) Minimum 5 ft (1524 mm) clear height over required floor area; ≥50% of required floor area must be ≥ 7 ft (2134 mm) Rooms with a sloped ceiling § R313 (Exceptions)
Basements (non‑habitable portions) 6 ft 8 in (2032 mm) minimum; obstructions allowed to 6 ft 4 in (1931 mm) Basements without habitable spaces; beams/obstructions exceptions § R313.1.1
Shower/tub area at showerhead 6 ft 8 in (2032 mm) over 30 in × 30 in (762 mm × 762 mm) area Clearance required above showerhead location § R313 (Exceptions)
Mezzanine clear height above & below 7 ft (2134 mm) Space above and below mezzanine construction § R314.2

(See the cited §§ for full text and surrounding context.)

How sloped & furred ceilings affect usable area

  • For a sloped ceiling, any portion of the room that is less than 5 feet high cannot be counted toward the room’s required habitable area; additionally, at least 50% of the required floor area must have a ceiling height of 7 feet or more. § R312.3 and § R313 (exceptions)
  • For a furred ceiling, portions under the furred (dropped) area below 7 feet do not count toward minimum habitable‑area calculations. § R312.3

Exceptions & special cases

  • Kitchens: are exempt from the 70 sq ft minimum area and the 7 ft minimum dimension requirement in R312. § R312.1 / § R312.2
  • Sloped ceilings: required floor area must include at least 50% at or above 7 ft, and no counted area can be under 5 ft (sloped ceiling rule). § R313 (Exceptions)
  • Basements: portions not containing habitable space must be at least 6 ft 8 in and obstructions (beams, ducts) can project down to 6 ft 4 in in basements. § R313.1.1
  • Habitable attics & existing buildings: when creating habitable attics or basement habitable space in existing buildings, the minimum ceiling heights are relaxed to 6 ft 8 in and 6 ft 4 in at obstructions as specified in § R313.1.2.
  • Mezzanines and sleeping lofts have their own height and area rules (see § R314 and § R315).

If your project is a conversion or an alteration in an existing building, check § R313.1.2 for limited reductions that may apply.

Common mistakes

  • Counting floor area under low sloped ceilings: many people include areas below 5 ft when computing the 70 sq ft—those portions do not count. § R312.3
  • Applying the 70 sq ft rule to kitchens—the code explicitly excepts kitchens from § R312.1.
  • Confusing CBC (Building Code) and CRC thresholds: the Building Code (CBC) has different ceilings and room rules for non‑residential occupancies (e.g., 7 ft 6 in occupiable spaces in CBC §1208.2), so verify you’re reading the CRC for one‑ and two‑family and Group R dwellings. (See related CBC sections if you work across both codes.)
  • Ignoring shower clearance: designers sometimes forget the minimum 6 ft 8 in over a 30 in × 30 in area at the showerhead. § R313 (Exceptions)

Worked example — applying the rules with numbers

Scenario: converting an attic into a bedroom. The proposed finished attic has a total floor area of 120 sq ft measured at the floor plane, but the ceiling slopes. The plan shows:

  • Area A: 60 sq ft where ceiling height ≥ 7 ft.
  • Area B: 40 sq ft where ceiling height is between 5 ft and 7 ft.
  • Area C: 20 sq ft where ceiling height < 5 ft.

Step 1 — usable area toward the 70 sq ft minimum:

  • Area C (< 5 ft) cannot be counted at all per § R312.3.
  • Area A (60 sq ft) + Area B (40 sq ft) = 100 sq ft of floor plane is above 5 ft. The portion under 5 ft (Area C) is excluded, leaving 100 sq ft available to count.

Step 2 — check the 50% rule for sloped ceilings:

  • The rule in § R313 (Exceptions) requires that at least 50% of the required floor area (here, the required floor area is 70 sq ft) be at or above 7 ft. That means at least 35 sq ft must be ≥ 7 ft.
  • We have Area A = 60 sq ft at ≥ 7 ft, which exceeds the 35 sq ft requirement.

Step 3 — conclusion:

  • Usable counted area = 100 sq ft (after excluding Area C). That exceeds the 70 sq ft minimum in § R312.1. The sloped‑ceiling 50% requirement is also satisfied. Therefore this attic conversion meets the area and ceiling‑height rules (subject to other code requirements such as egress, insulation, etc.). § R312.1 / § R313 (exceptions)

If Area A had been only 30 sq ft, the conversion would fail the 50%‑at‑7‑ft test even if total counted area exceeded 70 sq ft. Always run both the area and the sloped‑ceiling percentage checks.

Related provisions (quick reference)

  • § R314 — Mezzanines (clear heights above & below; area limits).
  • § R315 — Sleeping lofts (area and height limits separate from mezzanines).
  • § R316 — Habitable attics (planning and requirements for attics made habitable).
  • § R301 — Design criteria / limited‑density owner‑built rural dwellings exceptions referenced by R312.2.
  • § R325 — Natural light and ventilation requirements that often go with habitable‑room conversions.

Code references

Grounded in the retrieved California Residential Code — click a citation to read the verbatim passage:

  • CRC § 7.1 High relevance — show source text

    _

    R311.7 Carbon monoxide detection systems. Carbon monoxide detection systems shall be permitted to be used in lieu of carbon monoxide alarms and shall comply with Sections R311.7.1 through R311.7.4.

    R311.7.1 General. Household carbon monoxide detection systems shall comply with NFPA 72. Carbon monoxide detectors shall be listed in accordance with UL 2075.

    R311.7.2 Location. Carbon monoxide detectors shall be installed and maintained in the locations specified in Section R311.3 or NFPA 72.

    R311.7.3 Permanent fixture. Where a household carbon monoxide detection system is installed, it shall become a permanent fixture of the occupancy and owned by the homeowner.

    R311.7.4 Combination detectors. Combination carbon monoxide and smoke detectors installed in carbon monoxide detection systems in lieu of carbon monoxide detectors shall be listed in accordance with UL 268 and UL 2075.

    Combination carbon monoxide/smoke detectors shall comply with all requirements for listing and approval by the Office of the State Fire Marshal for smoke alarms.

    SECTION R312—MINIMUM ROOM AREAS

    R312.1 Minimum area. Habitable rooms shall have a floor area of not less than 70 square feet (6.5 m [2] ).

    Exception: Kitchens.

    R312.2 Minimum dimensions. Habitable rooms shall be not less than 7 feet (2134 mm) in any horizontal dimension.

    Exceptions:

    1. Kitchens.

    2. Limited-density owner-built rural dwellings. See Section R301.1.1.1.

    R312.3 Height effect on room area. Portions of a room with a sloping ceiling measuring less than 5 feet (1524 mm) or a furred ceiling measuring less than 7 feet (2134 mm) from the finished floor to the finished ceiling shall not be considered as contributing to the minimum required habitable area for that room.

    SECTION R313—CEILING HEIGHT

    R313.1 Minimum height. Habitable space, hallways and portions of basements containing these spaces shall have a ceiling height of not less than 7 feet (2134 mm). Bathrooms, toilet rooms and laundry rooms shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).

    Exceptions:

    1. For rooms with sloped ceilings, the required floor area of the room shall have a ceiling height of not less than 5 feet (1524 mm) and not less than 50 percent of the required floor area shall have a ceiling height of not less than 7 feet (2134 mm).
    2. The ceiling height above bathroom and toilet room fixtures shall be such that the fixture is capable of being used for its intended purpose. A shower or tub equipped with a showerhead shall have a ceiling height of not less than 6 feet 8 inches (2032 mm) above an area of not less than 30 inches (762 mm) by 30 inches (762 mm) at the showerhead.
    3. Beams, girders, ducts or other obstructions in basements containing habitable space shall be permitted to project to within 6 feet 4 inches (1931 mm) of the finished floor.
    4. Beams and girders spaced apart not less than 36 inches (914 mm) in clear finished width shall project not more than 78 inches (1981 mm) from the finished floor.
  • CRC § 1230.1.4 High relevance — show source text

    1230.1.4 Corridors. Corridors in living units shall be at least 8 feet (2438 mm) wide.

    1230.1.5 Living unit. A living unit shall be a self-contained unit containing locked sleeping rooms, single and double occupancy sleeping rooms or dormitories, dayroom space, toilet, wash basins, drinking fountains and showers commensurate to the number of youth housed. A living unit shall not be divided in a way that hinders direct access, supervision, immediate intervention or other action if needed. In juvenile halls, the number of youth housed in a living unit shall not exceed 30.

    1230.1.6 Locked sleeping rooms. Locked sleeping rooms shall be equipped with an individual or combination toilet, wash basin, mirror and drinking fountain. Doors to locked sleeping rooms shall swing outward or slide laterally.

    12-98 2025 CALIFORNIA BUILDING CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    INTERIOR ENVIRONMENT

    1230.1.7 Single occupancy sleeping rooms. Single occupancy sleeping rooms shall provide the following: 1. A minimum of 70 square feet (1.78 m [2] ) of floor area; 2. A minimum clear ceiling height of 8 feet (2438 mm); and 3. The door into this room shall swing outward or slide laterally and be provided with a view panel, a minimum of 144 square inches (92,903 mm [2] ), constructed of security glazing. 4. Contain a bed as specified in 1230.2.5.

    1230.1.8 Double occupancy sleeping rooms. Double occupancy sleeping rooms shall provide the following: 1. A minimum of 100 square feet (9.3 m [2] ) of floor area; 2. A minimum clear ceiling height of 8 feet (2438 mm) and a minimum width of 7 feet (2134 mm); and 3. The door into this room shall swing outward or slide laterally and be provided with a view panel, a minimum of 144 square inches (92,903 mm [2] ), constructed of security glazing. 4. Contain beds as specified in 1230.2.5.

    1230.1.9 Dormitories. Dormitories shall provide the following: 1. A minimum of 50 square feet (4.6 m [2] ) of floor area per youth with the minimum size of a dormitory being 200 square feet (18.6 m [2] ) of floor area and a minimum 8-foot (2438 mm) clear ceiling height; 2. Designed for no fewer than four youth; 3. Dormitories in juvenile halls shall be designed for no more than 30 youth; 4. Camps shall conform to Items 1 and 2. 1230.1.10 Dayrooms. Dayrooms shall contain 35 square feet (3.3 m [2] ) of floor area per youth, and contain tables and seating to accommodate the maximum numbers of youth allowed access at a given time. Access must be provided to toilets, wash basins, drink- ing fountains and showers as specified in Section 1230.2.

  • CRC § 1231.2.5 High relevance — show source text

    1231.2.5 Safety cell. A safety cell shall: 1. Contain a minimum of 48 square feet (4.5 m [2] ) of floor area with no one floor dimension being less than 6 feet (1829 mm) and a clear ceiling height of 8 feet (2438 mm) or more; 2. Be limited to one incarcerated person; 3. Contain a flushing ring toilet, capable of accepting solid waste, mounted flush with the floor, the controls for which must be located outside of the cell;

    4. Be padded as specified in Section 1231.3; 5. Be equipped with a variable intensity, security-type lighting fixture which is inaccessible to the occupant, control of which is located outside of the cell;

    6. Provide one or more vertical view panels not more than 4 inches (102 mm) wide nor less than 24 inches (610 mm) long which shall provide a view of the entire room; 7. Provide a food pass with lockable shutter, no more than 4 inches (102 mm) high, and located between 26 inches (660 mm) and 32 inches (813 mm) as measured from the bottom of the food pass to the floor; and 8. Any wall or ceiling mounted devices must be inaccessible to the occupant.

    1231.2.6 Single-occupancy cells. Single-occupancy cells shall: 1. Have a maximum capacity of one incarcerated person; 2. Contain a minimum of 60 square feet (5.6 m [2] ) of floor area in Type I facilities and 70 square feet (6.5 m [2] ) of floor area in Type II and Type III facilities; 3. Have a minimum clear ceiling height of 8 feet (2438 mm) and a minimum width of 6 feet (1829 mm); 4. Contain a toilet, wash basin and drinking fountain as specified in Section 1231.3; and 5. Contain a bunk, desk and seat as specified in Section 1231.3.

    Exception: A Type I facility does not require a desk and seat.

    1231.2.7 Double-occupancy cells. Double-occupancy cells shall: 1. Have a maximum capacity of two incarcerated people; 2. Contain a minimum of 60 square feet (5.6 m [2] ) of floor area in Type I facilities and 70 square feet (6.5 m [2] ) of floor area in Type II and Type III facilities; 3. Have a minimum clear ceiling height of 8 feet (2438 mm) and a minimum width of 6 feet (1829 mm); 4. Contain a toilet, wash basin and drinking fountain as specified in Section 1231.3; and 5. Contain two bunks, and at least one desk and seat as specified in Section 1231.3.

    Exception: A Type I facility does not require a desk and seat.

    1231.2.8 Dormitories. Dormitories shall:

  • CRC § 3-33 High relevance — show source text

    R304 Protection of Wood and Wood-Based Products

    Against Decay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33

    R305 Protection Against Subterranean Termites. . . . . . . 3-35

    R306 Flood-Resistant Construction. . . . . . . . . . . . . . . . . . . 3-36

    R307 Storm Shelters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40

    R308 Site Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40

    R309 Automatic Sprinkler Systems . . . . . . . . . . . . . . . . . . . 3-41

    R310 Smoke Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-54

    R311 Carbon Monoxide Alarms. . . . . . . . . . . . . . . . . . . . . . . 3-58

    R312 Minimum Room Areas . . . . . . . . . . . . . . . . . . . . . . . . . 3-59

    R313 Ceiling Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-59

    R314 Mezzanines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-60

    R315 Sleeping Lofts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-60

    R316 Habitable Attics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-61

    R317 Garages and Carports. . . . . . . . . . . . . . . . . . . . . . . . . . 3-61

    R318 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-62

    R319 Emergency Escape and Rescue Openings . . . . . . . . 3-65

    R320 Handrails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-67

    R321 Guards and Window Fall Protection . . . . . . . . . . . . . 3-67

    R322 Accessibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-68

    R323 Elevators and Platform Lifts . . . . . . . . . . . . . . . . . . . . 3-68

    R324 Glazing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-68

  • CRC § 1208.2 High relevance — show source text

    1208.2 Minimum ceiling heights. Occupiable spaces, habitable spaces and corridors shall have a ceiling height of not less than 7 feet 6 inches (2286 mm) above the finished floor. Bathrooms, toilet rooms, kitchens, storage rooms and laundry rooms shall have a ceiling height of not less than 7 feet (2134 mm) above the finished floor.

    Exceptions:

    1. In one- and two-family dwellings, beams or girders spaced not less than 4 feet (1219 mm) on center shall be permitted to project not more than 6 inches (152 mm) below the required ceiling height.
    2. If any room in a building has a sloped ceiling, the prescribed ceiling height for the room is required in one-half the area thereof. Any portion of the room measuring less than 5 feet (1524 mm) from the finished floor to the ceiling shall not be included in any computation of the minimum area thereof.
    3. The height of mezzanines and spaces below mezzanines shall be in accordance with Section 505.2.

    12-8 2025 CALIFORNIA BUILDING CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    INTERIOR ENVIRONMENT

    1. Corridors contained within a dwelling unit or sleeping unit in a Group R occupancy shall have a ceiling height of not less than 7 feet (2134 mm) above the finished floor.

    5. [OSHPD 1, 2, 3 & 5] Minimum ceiling heights shall comply with Section 1224.4.10. 6. [OSHPD 4] Minimum ceiling heights shall comply with Section 1227.8.

    1208.2.1 Furred ceiling. Any room with a furred ceiling shall be required to have the minimum ceiling height in two-thirds of the area thereof, but in no case shall the height of the furred ceiling be less than 7 feet (2134 mm). 1208.3 Dwelling unit size. Dwelling units shall have a minimum of 190 square feet (17.7 m [2] ) of habitable space. 1208.4 Room area. Every dwelling unit shall have not less than one room that shall have not less than 120 square feet (11.2 m [2] ) of net floor area. Sleeping units and other habitable rooms of a dwelling unit shall have a net floor area of not less than 70 square feet (6.5 m [2] ).

    Exception: Kitchens are not required to be of a minimum floor area.

    1208.5 Efficiency dwelling units. [HCD 1] Unless modified by local ordinance pursuant to Health and Safety Code Section 17958.1, effi- ciency dwelling units shall comply with the following:

    1. The unit’s habitable space shall comply with Sections 1208.1 through 1208.4.
    2. The unit shall be provided with a separate closet.
    3. For other than Accessible, adaptable dwelling units, the unit shall be provided with a kitchen sink, cooking appliance and refrigerator, each having a clear working space of not less than 30 inches (762 mm) in front. Light and ventilation conforming to this code shall be provided.
    4. The unit shall be provided with a separate bathroom containing a water closet, lavatory and bathtub or shower.

    SECTION 1209—ACCESS TO UNOCCUPIED SPACES

  • CRC § 1206.4 High relevance — show source text

    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), consis- tent 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 additional sound trans- mission requirements.

    SECTION 1207—ENHANCED CLASSROOM ACOUSTICS

    1207.1 General. Enhanced classroom acoustics, where required by this section, shall comply with Section 808 of ICC A117.1.

    1207.2 Where required. In Group E occupancies, enhanced classroom acoustics shall be provided in all classrooms with a volume of 20,000 cubic feet (566 m [3] ) or less.

    SECTION 1208—INTERIOR SPACE DIMENSIONS

    1208.1 Minimum room widths. Habitable spaces, other than a kitchen, shall be not less than 7 feet (2134 mm) in any plan dimension. Kitchens shall have a clear passageway of not less than 3 feet (914 mm) between counter fronts and appliances or counter fronts and walls.

    [HCD 1] For limited-density owner-built rural dwellings, there shall be no requirements for room dimensions, provided there is adequate light and ventilation and adequate means of egress.

    1208.2 Minimum ceiling heights. Occupiable spaces, habitable spaces and corridors shall have a ceiling height of not less than 7 feet 6 inches (2286 mm) above the finished floor. Bathrooms, toilet rooms, kitchens, storage rooms and laundry rooms shall have a ceiling height of not less than 7 feet (2134 mm) above the finished floor.

    Exceptions:

    1. In one- and two-family dwellings, beams or girders spaced not less than 4 feet (1219 mm) on center shall be permitted to project not more than 6 inches (152 mm) below the required ceiling height.
    2. If any room in a building has a sloped ceiling, the prescribed ceiling height for the room is required in one-half the area thereof. Any portion of the room measuring less than 5 feet (1524 mm) from the finished floor to the ceiling shall not be included in any computation of the minimum area thereof.
    3. The height of mezzanines and spaces below mezzanines shall be in accordance with Section 505.2.

    12-8 2025 CALIFORNIA BUILDING CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    INTERIOR ENVIRONMENT

    1. Corridors contained within a dwelling unit or sleeping unit in a Group R occupancy shall have a ceiling height of not less than 7 feet (2134 mm) above the finished floor.

    5. [OSHPD 1, 2, 3 & 5] Minimum ceiling heights shall comply with Section 1224.4.10. 6. [OSHPD 4] Minimum ceiling heights shall comply with Section 1227.8.

  • CRC § 1231.2.2 High relevance — show source text

    1231.2.2 Temporary holding cell or room. A temporary holding cell or room shall: 1. Contain a minimum of 10 square feet (0.93 m [2] ) of floor area per incarcerated person; 2. Be limited to no more than 16 incarcerated people; 3. Be no smaller than 40 square feet (3.7 m [2] ) and have a clear ceiling height of 8 feet (2438 mm) or more; 4. Contain seating to accommodate all incarcerated people as required in Section 1231.3; 5. Contain a toilet, wash basin and drinking fountain as specified in Section 1231.3; 6. Maximize visual supervision of incarcerated people by staff; and 7. When located in a temporary holding facility, the cell or room shall be equipped with a bunk if incarcerated people are to be held longer than 12 hours.

    1231.2.3 Temporary staging cell or room. A temporary staging cell or room shall: 1. Be constructed for the purpose of holding incarcerated people who have been classified and separated in accordance with Sections 1050 and 1053 of Title 15, Division 1, California Code of Regulations. 2. Be limited to holding incarcerated people up to four hours. 3. Be limited to no more than 80 incarcerated people. 4. Contain a minimum of 10 square feet (0.93 m [2] ) of floor area per incarcerated person and a clear ceiling height of 8 feet (2438 mm) or more.

    2025 CALIFORNIA BUILDING CODE 12-103

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    INTERIOR ENVIRONMENT

    5. Be no smaller than 160 square feet (14.9 m [2] ). 6. Contain seating to accommodate all incarcerated people as required in Section 1231.3. 7. Contain toilet, wash basin and drinking fountain as specified in Section 1231.3. 8. Maximize visual supervision of incarcerated people by staff.

    1231.2.4 Sobering cell. A sobering cell shall: 1. Contain a minimum of 20 square feet (1.9 m [2] ) of floor area per incarcerated person; 2. Be limited to eight incarcerated people; 3. Be no smaller than 60 square feet (5.6 m [2] ) and have a clear ceiling height of 8 feet (2438 mm) or more; 4. Contain a toilet, wash basin and drinking fountain as specified in Section 1231.3; 5. Have padded partitions located next to toilet fixture in such a manner that they provide support to the user; 6. Maximize visual supervision of incarcerated people by staff; 7. Be padded on the floor as specified in Section 1231.3; and 8. Have accessible a shower in the secure portion of the facility.

  • CRC § 1208.2.1 High relevance — show source text

    1208.2.1 Furred ceiling. Any room with a furred ceiling shall be required to have the minimum ceiling height in two-thirds of the area thereof, but in no case shall the height of the furred ceiling be less than 7 feet (2134 mm). 1208.3 Dwelling unit size. Dwelling units shall have a minimum of 190 square feet (17.7 m [2] ) of habitable space. 1208.4 Room area. Every dwelling unit shall have not less than one room that shall have not less than 120 square feet (11.2 m [2] ) of net floor area. Sleeping units and other habitable rooms of a dwelling unit shall have a net floor area of not less than 70 square feet (6.5 m [2] ).

    Exception: Kitchens are not required to be of a minimum floor area.

    1208.5 Efficiency dwelling units. [HCD 1] Unless modified by local ordinance pursuant to Health and Safety Code Section 17958.1, effi- ciency dwelling units shall comply with the following:

    1. The unit’s habitable space shall comply with Sections 1208.1 through 1208.4.
    2. The unit shall be provided with a separate closet.
    3. For other than Accessible, adaptable dwelling units, the unit shall be provided with a kitchen sink, cooking appliance and refrigerator, each having a clear working space of not less than 30 inches (762 mm) in front. Light and ventilation conforming to this code shall be provided.
    4. The unit shall be provided with a separate bathroom containing a water closet, lavatory and bathtub or shower.

    SECTION 1209—ACCESS TO UNOCCUPIED SPACES

    1209.1 Crawl spaces. Crawl spaces shall be provided with not less than one access opening that shall be not less than 18 inches by 24 inches (457 mm by 610 mm).

    1209.1.1 [SPCB] Accessible under-floor areas shall be provided with an 18-inch by 24-inch (457 mm by 610 mm) access crawl hole. Pipes, ducts and other nonstructural construction shall not interfere with the accessibility to or within under-floor areas.

    1209.2 Attic spaces. An opening not less than 20 inches by 30 inches (559 mm by 762 mm) shall be provided to any attic area having a clear height of over 30 inches (762 mm). Clear headroom of not less than 30 inches (762 mm) shall be provided in the attic space at or above the access opening.

    1209.3 Mechanical appliances. Access to mechanical appliances installed in under-floor areas, in attic spaces and on roofs or elevated structures shall be in accordance with the California Mechanical Code .

    SECTION 1210—TOILET AND BATHROOM REQUIREMENTS

    [P] 1210.1 Required fixtures. The number and type of plumbing fixtures provided in any occupancy shall comply with the California Plumbing Code.

    [P] 1210.2 Finish materials. Walls, floors and partitions in toilet and bathrooms shall comply with Sections 1210.2.1 through 1210.2.5.

    [OSHPD 1, 2, 3 & 5] Facilities subject to OSHPD 1, 2, 3 & 5 shall also comply with Section 1224.4.11.

  • CRC § 1.1 High relevance — show source text

    SECTION R313—CEILING HEIGHT

    R313.1 Minimum height. Habitable space, hallways and portions of basements containing these spaces shall have a ceiling height of not less than 7 feet (2134 mm). Bathrooms, toilet rooms and laundry rooms shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).

    Exceptions:

    1. For rooms with sloped ceilings, the required floor area of the room shall have a ceiling height of not less than 5 feet (1524 mm) and not less than 50 percent of the required floor area shall have a ceiling height of not less than 7 feet (2134 mm).
    2. The ceiling height above bathroom and toilet room fixtures shall be such that the fixture is capable of being used for its intended purpose. A shower or tub equipped with a showerhead shall have a ceiling height of not less than 6 feet 8 inches (2032 mm) above an area of not less than 30 inches (762 mm) by 30 inches (762 mm) at the showerhead.
    3. Beams, girders, ducts or other obstructions in basements containing habitable space shall be permitted to project to within 6 feet 4 inches (1931 mm) of the finished floor.
    4. Beams and girders spaced apart not less than 36 inches (914 mm) in clear finished width shall project not more than 78 inches (1981 mm) from the finished floor.

    R313.1.1 Basements. Portions of basements that do not contain habitable space or hallways shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).

    Exception: At beams, girders, ducts or other obstructions, the ceiling height shall be not less than 6 feet 4 inches (1931 mm) from the finished floor.

    2025 CALIFORNIA RESIDENTIAL CODE 3-59

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    BUILDING PLANNING

    R313.1.2 Habitable attics and basements in existing buildings. Where a habitable attic or habitable space in a basement is created in an existing building, ceiling height shall not be less than 6 feet 8 inches (2032 mm). Bathrooms, toilet rooms and laundry rooms shall have a ceiling height of not less than 6 feet 4 inches (1930 mm).

    Exceptions:

    1. For rooms with sloped ceilings, the required floor area of the room shall have a ceiling height of not less than 5 feet (1524 mm) and not less than 50 percent of the required floor area shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).
    2. At beams, girders, ducts or other obstructions, the ceiling height shall be not less than 6 feet 4 inches (1930 mm) from the finished floor.

    SECTION R314—MEZZANINES

    R314.1 General. Mezzanines shall comply with Sections R314.2 through R314.5.

    Exception: Sleeping lofts in dwelling units and sleeping units shall be permitted to comply with Section R315, subject to the limitations in Section R315.2.

    R314.2 Mezzanines. The clear height above and below mezzanine floor construction shall be not less than 7 feet (2134 mm).

  • CRC § 503.1. High relevance — show source text

    P SLEEPING LOFTS

    The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency or referenced in the adopting ordinance.

    User notes:

    About this appendix: Appendix P provides allowances for, and limitations on, spaces intended to be used as sleeping lofts, while differentiating these spaces from mezzanines and other habitable space.

    ICC code development note: Code change proposals to sections in this appendix will be considered by the IBC—General Code Development Committee

    during the 2025 (Group B) Code Development Cycle.

    SECTION P101—GENERAL

    P101.1 General. Where provided in Group R occupancies, sleeping lofts shall comply with the provisions of this code, except as modified by this appendix. Sleeping lofts constructed in compliance with this appendix shall be considered a portion of the story below. Such sleeping lofts shall not contribute to either the building area or number of stories as regulated by Section 503.1. The sleeping loft floor area shall be included in determining the fire area.

    The following sleeping lofts are exempt from compliance with this appendix:

    1. Sleeping lofts with a maximum depth of less than 3 feet (914 mm).
    2. Sleeping lofts with a floor area of less than 35 square feet (3.3 m [2] ).
    3. Sleeping lofts not provided with a permanent means of egress.

    P101.2 Sleeping loft limitations. Sleeping lofts shall comply with the following:

    1. The sleeping loft floor area shall be less than 70 square feet (6.5 m [2] ).
    2. The sleeping loft ceiling height shall not exceed 7 feet (2134 mm) for more than one-half of the sleeping loft floor area.

    The provisions of this appendix shall not apply to sleeping lofts that do not comply with Items 1 and 2.

    P101.3 Sleeping loft ceiling height. The clear height below the sleeping loft floor construction shall be not less than 7 feet (2134 mm). The ceiling height above the finished floor of the sleeping loft shall be not less than 3 feet (914 mm). Portions of the sleeping loft with a sloped ceiling measuring less than 3 feet (914 mm) from the finished floor to the finished ceiling shall not contribute to the sleeping loft floor area.

    P101.4 Sleeping loft area. The aggregate area of all sleeping lofts and mezzanines within a room shall comply with Section 505.2.1.

    Exception: The area of a single sleeping loft shall not be greater than two-thirds of the area of the room in which it is located, provided that no other sleeping lofts or mezzanines are open to the room in which the sleeping loft is located.

    SECTION P102—DEFINITIONS

    P102.1 General. The following term shall, for the purposes of this appendix, have the meaning shown herein. Refer to Chapter 2 for general definitions.

    SLEEPING LOFT. A space on an intermediate level or levels between the floor and ceiling of a Group R occupancy dwelling or sleeping unit, open on one or more sides to the room in which the sleeping loft is located.

    SECTION P103—MEANS OF EGRESS

    P103.1 General. Where a permanent means of egress is provided for sleeping lofts, the means of egress shall comply with Chapter 10 of this code, as modified by Sections P103.2 through P103.6.

  • CRC § 2603.10 High relevance — show source text

    2603.10

    2025 CALIFORNIA BUILDING CODE 35-39

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    REFERENCED STANDARDS

    SDI Steel Deck Institute, 2661 Clearview Road #3, Allison Park, PA 15101

    ANSI/SDI QA/QC—2022: Standard for Quality Control and Quality Assurance for Installation of Steel Deck

    1705.2.3

    ANSI/SDI SD—2022: Standard for Steel Deck

    2208.1

    SFM State of California, Department of Forestry and Fire Protection, Office of the State Fire Marshal, P.O. Box 944246, Sacramento, CA 94246-2460

    12-3: Releasing Systems for Security Bars in Dwellings

    1029.4

    12-7-3: Fire-testing Furnaces

    NA

    12-7A-1: Exterior Wall Siding and Sheathing

    703A.7, 707A.2

    12-7A-2: Exterior Window

    703A.7, 708A.2.1

    12-7A-3: Under Eave

    703A.7, 707A.8

    12-7A-4: Decking:

    703A.7, 709A.3

    12-7A-4A: Decking Alternate Method A

    703A.7, 709A.3

    12-7A-5: Ignition Resistant Building Material

    703A.7, 709A.3

    12-8-100: Room Fire Tests for Wall and Ceiling Materials

    NA

    12-10-1: Power Operated Exit Doors

    NA

    12-10-2: Single Point Latching or Locking Devices

    NA

    12-10-3: Emergency Exit and Panic Hardware

    NA

    (The Office of the State Fire Marshal standards referred to above are found in the California Code of Regulations, Title 24, Part 12.):

    SJI Steel Joist Institute, 140 Evans Street, Suite 203, Florence, SC 29501

    SJI 100—2020: Standard Specification for K-Series, LH-Series, and DLH-Series Open Web Steel Joists and for Joist Girders

    1604.3.3, 2207.1, 2207.2, 2207.3, 2207.4, 2207.5

    SJI 200—2015: Standard Specification for CJ-Series Composite Steel Joists

    1604.3.3, 2207.1, 2207.2, 2207.3, 2207.4, 2207.5

    SPRI Single-Ply Roofing Industry, 465 Waverly Oaks Road, Suite 421, Waltham, MA 02452

    ANSI/SPRI GT-1—2022: Test Standard for External Gutter Systems

    1504.6.1, 1511.7.6.1

    ANSI/SPRI RP-4—2019: Wind Design Standard for Ballasted Single-ply Roofing Systems

    1504.5

    ANSI/SPRI VF-1—2021: External Fire Design Standard for Vegetative Roofs

  • CRC § 3.3 High relevance — show source text

    SECTION R315—SLEEPING LOFTS

    R315.1 Sleeping lofts. Where provided in dwelling units or sleeping units, sleeping lofts shall comply with this code as modified by Sections R315.2 through R315.5. Sleeping lofts constructed in compliance with this section shall be considered a portion of the story below. Such sleeping lofts shall not contribute to the number of stories as regulated by this code.

    Exceptions: Sleeping lofts need not comply with Section R315 where they meet any of the following conditions:

    1. The sleeping loft has a depth of less than 3 feet (914 mm).
    2. The sleeping loft has a floor area of less than 35 square feet (3.3 m [2] ).
    3. The sleeping loft is not provided with a permanent means of egress.

    R315.2 Sleeping loft limitations. Sleeping lofts shall comply with the following conditions:

    1. The sleeping loft floor area shall be less than 70 square feet (6.5 m [2] ).
    2. The sleeping loft ceiling height shall not exceed 7 feet (2134 mm) for more than one-half of the sleeping loft floor area.

    R315.3 Sleeping loft ceiling height. The clear height below the sleeping loft floor construction shall not be less than 7 feet (2134 mm). The ceiling height above the finished floor of the sleeping loft shall not be less than 3 feet (914 mm). Spaces adjacent to the sleeping loft with a sloped ceiling measuring less than 3 feet (914 mm) from the finished floor to the finished ceiling shall not contribute to the sleeping loft floor area.

    R315.4 Sleeping loft area. The aggregate area of all sleeping lofts and mezzanines within a room shall comply with Section R314.3.

    Exception: The area of a single sleeping loft located within a dwelling unit or sleeping unit equipped with an automatic sprinkler system in accordance with Section R309 shall not be greater than two-thirds of the area of the room in which it is located, provided that no other sleeping lofts or mezzanines are open to the room in which the sleeping loft is located.

    R315.5 Permanent egress for sleeping lofts. A permanent means of egress shall be provided for sleeping lofts. The means of egress shall comply with Section R318 as modified by Sections R315.5.1 through R315.5.3.

    R315.5.1 Ceiling height at sleeping loft means of egress. A ceiling height of not less than 3 feet (914 mm) shall be provided for the entire width of the means of egress from the sleeping loft.

    R315.5.2 Stairways. Stairways providing egress from sleeping lofts shall be permitted to comply with Sections R315.5.2.1 through R315.5.2.3.

    3-60 2025 CALIFORNIA RESIDENTIAL CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    BUILDING PLANNING

    R315.5.2.1 Width. Stairways providing egress from a sleeping loft shall not be less than 17 inches (432 mm) in clear width at or above the handrail. The width below the handrail shall be not less than 20 inches (508 mm).

Frequently asked questions

Can a kitchen count toward the 70 sq ft habitable‑room minimum?

No. Kitchens are explicitly excepted from the 70 sq ft minimum in § R312.1; do not apply the 70 sq ft rule to kitchens.

If part of a room has only 4 ft of ceiling height, can I include that area?

No. Portions of a room with sloped ceilings under 5 ft or furred ceilings under 7 ft are not counted toward the required habitable area per § R312.3.

What is the minimum ceiling height for a bathroom?

Bathrooms, toilet rooms and laundry rooms require a minimum ceiling height of 6 ft 8 in in new construction under § R313.1 (with specific shower clearance requirements also noted).

Do mezzanines have the same height rules?

Mezzanines require 7 ft of clear height both above and below the mezzanine floor construction; see § R314.2 for details.

Do attic conversions in existing buildings have the same height requirements?

There are relaxed minimums for habitable attics and basements when created in existing buildings: see § R313.1.2 — generally 6 ft 8 in minimum with reduced heights allowable at obstructions.

More in California Residential Code

Ask about the CRC

Get cited, plain-English answers on the California Residential Code for your project — any code section, any scenario.

Start Free Trial

Related in the CRC

What glazing and exhaust requirements apply to bathrooms and similar rooms?

What are the natural light and natural ventilation requirements for habitable rooms?

Light, Ventilation & Environmental Comfort

California Residential Code