CALGreen · California Green Building Standards Code (CALGreen)

What does the Department of Housing and Community Development (HCD) regulate under CALGreen?

If your project is an apartment, motel, dormitory, shelter, factory‑built housing, or similar multi‑unit/residential building, CALGreen’s residential requirements apply and are enforced by your local building department or HCD under **§ 104.1**; detached single‑family homes are typically handled under the California Residential Code.

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Last reviewed: July 6, 2026

What the code requires — 2–4 sentences

The Department of Housing and Community Development (HCD) is responsible for the CALGreen requirements that apply to housing construction: hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and related accessory buildings, facilities and uses. These applications and the enforcing agency assignment are set out in § 104.1 of CALGreen. Enforcement is by the local building department or HCD and the section lists the statutory authorities that enable HCD to adopt and enforce these provisions.

The single most important rule: if your project is any of the listed residential/housing types in § 104.1, CALGreen’s residential measures apply and enforcement is through the local building department or HCD.

Requirements in detail

Scope (who and what)

  • Defined scope: Housing construction — includes hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing, and other dwellings containing sleeping accommodations with or without common toilet or cooking facilities, plus accessory buildings, facilities and uses. See § 104.1.
  • Enforcing agency: Local building department or the Department of Housing and Community Development (per § 104.1).

Decision-relevant table

Decision item Value / scope (what to check) Code Reference
Which occupancies are covered Hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing, accessory buildings § 104.1
Who enforces Local building department or HCD § 104.1
Applicable CALGreen chapters Residential mandatory measures (Chapter 4) for covered occupancies Chapter 4; see CHAPTER 4 — Residential Mandatory Measures (CALGreen)
Graywater systems (where HCD applies) Graywater systems regulation may be shared with Dept. of Water Resources and HCD for some occupancies Section references in Chapter 1 (see matrix) and § 104.1 note on graywater cross-reference
Alternate approvals Local building departments may approve alternates; HCD may also approve alternates for HCD-scoped buildings (tests or evidence may be required) Alternate-approval rules (HCD / local) — see plumbing/building code cross-references and HCD approval language

Where the residential mandatory measures live

  • The specific minimum green building requirements for these occupancies are found in the residential chapters (for example, CHAPTER 4 — Residential Mandatory Measures) and the Matrix Adoption Tables that identify agency adoptions. For reference see the CALGreen chapter listing and Chapter 4 heading.

Exceptions & special cases

  • Detached one- and two‑family dwellings and townhouses are generally not under HCD for these CALGreen adoptions — those are addressed in the California Residential Code; CALGreen indicates that note explicitly. Do not assume HCD covers single‑family detached homes by default.
  • Some specialized applications (e.g., public schools, state-owned buildings, hospitals) are regulated by other state agencies (Division of the State Architect, Office of Statewide Health Planning and Development, etc.); check the agency matrix in Chapter 1 to confirm jurisdiction. See § 103 and § 105 for other agencies' scopes.
  • Mobilehome parks / special-occupancy parks and permanent buildings within those parks have distinct HCD scopes sometimes listed as HCD‑2 in matrix tables — confirm which HCD subcategory applies to your project.

Common mistakes

  • Mistake: "HCD covers single‑family detached homes." Reality: CALGreen and the model codes explicitly direct users to the California Residential Code for detached one‑ and two‑family dwellings — HCD’s § 104.1 covers the broader housing categories listed, not typical detached single‑family houses.
  • Mistake: "Assuming a single statewide enforcement path." Reality: enforcement is often by the local building department, not HCD directly; HCD remains an enforcing agency option and may approve alternates. Check local enforcement authority early.
  • Mistake: "Applying non-residential CALGreen measures." Reality: use the Matrix Adoption Tables and chapter headings to apply the correct chapter (residential vs. nonresidential) for the HCD-scoped occupancy. See CHAPTER 4 for residential mandatory measures.

Worked example

Scenario: You are designing a new 12‑unit apartment building (Group R‑2 style occupancy) with an attached laundry room and a shared mail room. What applies and who enforces?

  1. Identify occupancy: a multi‑unit residential building (apartment) — this is explicitly listed in § 104.1 as housing construction covered by HCD scope. Action: treat the project as an HCD‑scoped residential project.
  2. Enforcement: submit plans to the local building department (typical) — they enforce CALGreen residential provisions for HCD‑scoped occupancies, or the local department may defer to HCD per statute. Action: confirm with your local building official whether they or HCD will be the enforcing agency.
  3. Applicable CALGreen requirements: follow the residential mandatory measures (CHAPTER 4) — water efficiency, indoor air quality, material conservation, EV‑ready requirements where applicable, etc. For example, Chapter 4 lists water‑efficient fixtures and mandatory construction waste diversion requirements for residential projects. Action: use Chapter 4 checklists in plan review and inspection.
  4. Alternates or deviations: if you propose an alternate compliance approach (e.g., a different plumbing fixture strategy), the local building department may approve alternates; HCD can also approve alternates and may require tests or evidence to substantiate equivalence. Action: prepare performance data or test reports when seeking alternate approvals.

Numeric illustration (simple): the project is 12 units — it is not a detached single‑family house, so CALGreen Chapter 4 mandatory residential measures apply and the plan reviewer must check the Matrix Adoption Table for any HCD‑specific adoption notes and the local enforcement path.

Related provisions

  • § 104.1 — Department of Housing and Community Development (scope for housing construction and enforcing agency).
  • § 103.1 — Building Standards Commission adoptions and cases where BSC‑CG adopts measures (useful when no state agency has authority).
  • § 101.3 / 101.3.1 — General scope and list of state‑regulated buildings (helps confirm when state agency adoptions apply).
  • CHAPTER 4 — Residential Mandatory Measures (where the specific green building requirements for HCD‑scoped occupancies are located).
  • HCD alternate‑approval rules and local enforcement procedures (plumbing/building code cross‑references describing HCD/local approval of alternates).

Code references

Grounded in the retrieved California Green Building Standards Code (CALGreen) — click a citation to read the verbatim passage:

  • CALGreen § 101.4 High relevance — show source text

    When adopted by a state agency, the provisions of this code shall be enforced by the appropriate enforcing agency, but only to the extent of authority granted to such agency by statute.

    1. State-owned buildings, including buildings constructed by the Trustees of the California State University, and to the extent permitted by California law, buildings designed and constructed by the Regents of the University of California and regulated by the Building Standards Commission. See Section 103 for additional scoping provisions.

    2. Energy efficiency standards regulated by the California Energy Commission.

    3. All residential buildings constructed throughout the State of California, including but not limited to, hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilets or cooking facilities regulated by the Department of Housing and Community Development. See Section 104 for additional scoping provisions.

    4. Public elementary and secondary schools, and community college buildings regulated by the Division of the State Architect. See Section 105 for additional scoping provisions.

    5. Qualified historical buildings and structures and their associated sites regulated by the State Historical Building Safety Board within the Division of the State Architect.

    6. General acute care hospitals, acute psychiatric hospitals, skilled nursing and/or intermediate care facilities, clinics licensed by the Department of Public Health and correctional treatment centers regulated by the Office of Statewide Health Planning and Development. See Section 106 for additional scoping provisions.

    7. Graywater systems regulated by the Department of Water Resources and the Department of Housing and Community Development.

    8. Green building standards for occupancies where no state agency has authority or expertise, adopted by the California Building Standards Commission. See Section 103 for additional scoping provisions.

    101.4 Appendices. Provisions contained in the appendices of this code are not mandatory unless specifically adopted by a city, county, or city and county in compliance with Health and Safety Code Sections 18930 and 18941.5, respectively, for Building Standards Law; Health and Safety Code Section 17950 for State Housing Law; and Health and Safety Code Section 13869.7 for Fire Protection Districts. See Section 101.7 of this code.

    101.5 Referenced codes and standards. The codes and standards referenced elsewhere in this code shall be considered part of the requirements of this code to the prescribed extent of each such reference.

    101.5.1 Building. The provisions of the California Building Code, California Residential Code and California Existing Building Code, as applicable, shall apply to the construction, alteration, movement, enlargement, replacement, repair, use and occupancy, location, maintenance, removal and demolition of every structure or any appurtenances connected or attached to such buildings or structures.

    101.5.2 Electrical. The provisions of the California Electrical Code shall apply to the installation of electrical systems, including but not limited to, alterations, repair, replacement, equipment, appliances, fixtures, fittings and appurtenances thereto.

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    101.5.3 Mechanical. The provisions of the California Mechanical Code shall apply to the installation, alterations, repair and replacement of mechanical systems, including equipment, appliances, fixtures, fittings and/or appurtenances, including ventilating, heating, cooling, air-conditioning and refrigeration systems, incinerators and other energy-related systems.

  • CALGreen § 103.1 High relevance — show source text

    SECTION 103—BUILDING STANDARDS COMMISSION

    103.1 BSC-CG. Specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

    1. Application— All occupancies where no state agency has the authority to adopt green building standards applicable to those occupancies. Enforcing agency— State or local agency specified by the applicable provisions of law. Authority cited— Health and Safety Code Sections 18930.5(a), 18938 and 18940.5. Reference— Health and Safety Code, Division 13, Part 2.5, commencing with Section 18901.
    2. Graywater systems. The construction, installation and alteration of graywater systems for indoor and outdoor uses in nonresidential occupancies. Application— All occupancies where no state agency has the authority to adopt green building standards applicable to those occupancies. Enforcing agency— State or local agency specified by the applicable provisions of law. Authority cited— Health and Safety Code Section 18941.8. Reference— Health and Safety Code Section 18941.8.

    103.1.1 Adopting agency identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym BSC-CG.

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    SECTION 104—DEPARTMENT OF HOUSING AND COMMUNITY DEVELOPMENT

    104.1 Scope. Specific scope of application of the agency responsible for enforcement, the enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

    1. Housing construction. Application— Hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilet or cooking facilities including accessory buildings, facilities and uses thereto. Enforcing agency— Local building department or the Department of Housing and Community Development. Authority cited— Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17922.15, 17926, 17927, 17928, 17958.12, 18938.3, 18944.11 and 19990; and Government Code Section

    12955.1.

  • CALGreen § 101.1 High relevance — show source text

    1 ADMINISTRATION

    SECTION 101—GENERAL

    101.1 Title. These regulations shall be known as the California Green Building Standards Code, may be cited as such, and will be referred to herein as “this code.” It is intended that it shall also be known as the CALGreen Code. The California Green Building Stan- dards Code is Part 11 of thirteen parts of the official compilation and publication of the adoption, amendment and repeal of building regulations to the California Code of Regulations, Title 24, also referred to as the California Building Standards Code.

    101.2 Purpose. The purpose of this code is to improve public health, safety and general welfare by enhancing the design and construction of buildings through the use of building concepts having a reduced negative impact or positive environmental impact and encouraging sustainable construction practices in the following categories:

    1. Planning and design.
    2. Energy efficiency.
    3. Water efficiency and conservation.
    4. Material conservation and resource efficiency.
    5. Environmental quality.

    101.3 Scope. The provisions of this code shall apply to the planning, design, operation, construction, use and occupancy of every newly constructed building or structure, unless otherwise indicated in this code, throughout the State of California.

    It is not the intent that this code substitute or be identified as meeting the certification requirements of any green building

    program.

    101.3.1 State-regulated buildings, structures and applications. Provisions of this code shall apply to the following buildings, structures and applications regulated by state agencies as specified in Sections 103 through 106, except where modified by local ordinance pursuant to Section 101.7. When adopted by a state agency, the provisions of this code shall be enforced by the appropriate enforcing agency, but only to the extent of authority granted to such agency by statute.

    1. State-owned buildings, including buildings constructed by the Trustees of the California State University, and to the extent permitted by California law, buildings designed and constructed by the Regents of the University of California and regulated by the Building Standards Commission. See Section 103 for additional scoping provisions.

    2. Energy efficiency standards regulated by the California Energy Commission.

    3. All residential buildings constructed throughout the State of California, including but not limited to, hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilets or cooking facilities regulated by the Department of Housing and Community Development. See Section 104 for additional scoping provisions.

    4. Public elementary and secondary schools, and community college buildings regulated by the Division of the State Architect. See Section 105 for additional scoping provisions.

    5. Qualified historical buildings and structures and their associated sites regulated by the State Historical Building Safety Board within the Division of the State Architect.

    6. General acute care hospitals, acute psychiatric hospitals, skilled nursing and/or intermediate care facilities, clinics licensed by the Department of Public Health and correctional treatment centers regulated by the Office of Statewide Health Planning and Development. See Section 106 for additional scoping provisions.

    7. Graywater systems regulated by the Department of Water Resources and the Department of Housing and Community Development.

    8. Green building standards for occupancies where no state agency has authority or expertise, adopted by the California Building Standards Commission. See Section 103 for additional scoping provisions.

  • CALGreen § 1.1.12 High relevance — show source text

    Note: Matrix Adoption Tables at the front of each chapter may aid the code user in determining which chapter or sections within a chap- ter are applicable to buildings under the authority of a specific state agency, but they are not to be considered regulatory.

    1.1.12 Validity. If any chapter, section, subsection, sentence, clause or phrase of this code is for any reason held to be unconstitutional, contrary to statute, exceeding the authority of the state as stipulated by statutes or otherwise inoperative, such decision shall not affect the validity of the remaining portion of this code.

    SECTION 1.2—RESERVED

    SECTION 1.3—RESERVED

    SECTION 1.4—RESERVED

    SECTION 1.5—RESERVED

    SECTION 1.6—RESERVED

    SECTION 1.7—RESERVED

    SECTION 1.8—DEPARTMENT OF HOUSING AND COMMUNITY DEVELOPMENT (HCD)

    1.8.1 Purpose. The purpose of this code is to establish the minimum requirements necessary to protect the health, safety and general welfare of the occupants and the public by governing accessibility, erection, construction, reconstruction, enlargement, conversion, alteration, repair, moving, removal, demolition, occupancy, use, height, court, area, sanitation, ventilation, maintenance and safety to life and property from fire and other hazards attributed to the built environment.

    SECTION 1.8.2—AUTHORITY AND ABBREVIATIONS

    1.8.2.1 General. The Department of Housing and Community Development is authorized by law to promulgate and adopt building stan- dards and regulations for several types of building applications. The applications under the authority of the Department of Housing and Community Development are listed in Sections 1.8.2.1.1 through 1.8.2.1.3.

    1.8.2.1.1 Housing construction.

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    Application— Hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilet or cooking facilities including accessory buildings, facilities and uses thereto. Sections of this code which pertain to applications listed in this section are identified using the abbreviation “HCD 1.”

    Enforcing agency— Local building department or the Department of Housing and Community Development.

    Authority cited— Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17926, 17927, 17928, 17958.12, 18938.3, 18944.11 and 19990; and Government Code Section 12955.1.

  • CALGreen § 1.3 High relevance — show source text

    SECTION 1.3—BOARD OF STATE AND COMMUNITY CORRECTIONS

    RESERVED

    SECTION 1.4—DEPARTMENT OF CONSUMER AFFAIRS

    RESERVED

    SECTION 1.5—CALIFORNIA ENERGY COMMISSION

    RESERVED

    SECTION 1.6—DEPARTMENT OF FOOD AND AGRICULTURE

    RESERVED

    SECTION 1.7—DEPARTMENT OF PUBLIC HEALTH

    RESERVED

    SECTION 1.8—DEPARTMENT OF HOUSING AND COMMUNITY DEVELOPMENT

    1.8.1 Purpose. The purpose of this code is to establish the minimum requirements necessary to protect the health, safety and general welfare of the occupants and the public by governing accessibility, erection, construction, reconstruction, enlargement, conversion, alteration, repair, moving, removal, demolition, occupancy, use, height, court, area, sanitation, ventilation, maintenance and safety to life and property from fire and other hazards attributed to the built environment.

    SECTION 1.8.2—AUTHORITY AND ABBREVIATIONS

    1.8.2.1 General. The Department of Housing and Community Development is authorized by law to promulgate and adopt building standards and regulations for several types of building applications. The applications under the authority of the Department of Housing and Community Development are listed in Sections 1.8.2.1.1 through 1.8.2.1.3.

    Note: See the California Residential Code for detached one-and two-family dwellings and townhouses.

    1.8.2.1.1 Housing construction.

    Application— Hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilet or cooking facilities including accessory buildings, facilities and uses thereto. Sections of this code which pertain to applications listed in this section are identified using the abbreviation “HCD 1.”

    Enforcing agency— Local building department or the Department of Housing and Community Development.

    Authority cited— Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17922.15, 17926, 17927, 17928, 17958.12, 18938.3, 18944.11 and 19990; and Government Code Section 12955.1.

  • CALGreen § 2.1 High relevance — show source text

    Application – Permanent buildings, and permanent accessory buildings or structures, constructed within mobilehome parks and special occupancy parks that are under the control and ownership of the park operator. Sections of this code which per- tain to applications listed in this section are identi- fied using the abbreviation “HCD 2”.

    Enforcing Agency – The Department of Housing and Community Development, local building department or other local agency that has assumed responsibility for the enforcement of Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200 for mobilehome parks and Health and Safety Code, Division 13, Part 2.3, com- mencing with Section 18860 for special occupancy parks.

    Authority Cited – Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17922.15, 17926, 17927, 17928, 17958.12, 18552, 18554, 18620, 18630, 18640, 18670, 18690, 18691, 18865, 18871.3, 18871.4, 18873, 18873.1 through 18873.5, 18938.3, 18944.11, and 19990; and Gov- ernment Code Section 12955.1.

    References – Health and Safety Code Sections 17000 through 17062.5, 17910 through 17995.5, 18200 through 18700, 18860 through 18874, 18938.6, 18941, 19890, 19891, 19892 and 19960 through 19997; Civil Code Sections 1101.4, 1101.5 and 1954.201; and Government Code Sections 12955.1 and 12955.1.1. California Code of Regulations, Title 20, Sections 1605.1, 1605.3 and 1607; and Title 25, Sections 1042 and 2042.

    1.8.3 Local Enforcing Agency.

    1.8.3.1 Duties and Powers. The building department of every city, county, or city and county shall enforce all the provisions of law, this code, and the other rules and reg- ulations promulgated by the Department of Housing and Community Development pertaining to the installation, erection, construction, reconstruction, movement, enlargement, conversion, alteration, repair, removal, demolition, or arrangement of apartments, condomini- ums, hotels, motels, lodging houses, and dwellings, including accessory buildings, facilities, and uses thereto.

    8 2025 CALIFORNIA PLUMBING CODE

    ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

    DIVISION I CALIFORNIA ADMINISTRATION

  • CALGreen § 18941.8. High relevance — show source text

    Authority cited— Health and Safety Code Section 18941.8. Reference— Health and Safety Code Section 18941.8.

    103.1.1 Adopting agency identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym BSC-CG.

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    SECTION 104—DEPARTMENT OF HOUSING AND COMMUNITY DEVELOPMENT

    104.1 Scope. Specific scope of application of the agency responsible for enforcement, the enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

    1. Housing construction. Application— Hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilet or cooking facilities including accessory buildings, facilities and uses thereto. Enforcing agency— Local building department or the Department of Housing and Community Development. Authority cited— Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17922.15, 17926, 17927, 17928, 17958.12, 18938.3, 18944.11 and 19990; and Government Code Section

    12955.1.

    Reference— Business and Professions Code Division 5; Health and Safety Code Sections 17000 through 17062.5, 17910 through 17995.5, 18200 through 18700, 18860 through 18874, 18938.6, 18941, 19890, 19891, 19892 and 19960 through 19997; Civil Code Sections 832, 1101.4, 1101.5, 1954.201, 1954.202 and 5551; Government Code Sections 8698.4, 12955.1 and 12955.1.1; and California Code of Regulations, Title 20, Sections 1605.1, 1605.3 and 1607.

    SECTION 105—DIVISION OF THE STATE ARCHITECT

    105.1 Specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

    105.1.1 Application—Public elementary and secondary schools and community colleges. New building construction and site work on a new or existing site.

    Note: The Application of Standards outlined in Title 24, Part 6 supersedes the above application as it applies to the California Energy Code.

    Enforcing agency— The Division of the State Architect-Structural Safety (DSA-SS) has been delegated the responsibility and authority by the Department of General Services to review and approve the design and observe the construction of public elementary and secondary schools, and community colleges.

    Authority cited— Education Code Sections 17310 and 81142.

    Reference— Education Code Sections 17280 through 17317, and 81130 through 81147.

  • CALGreen § 1-5 Medium relevance — show source text

    102 Construction Documents

    and Installation Verification . . . . . . . . . . . . . . . . . . . .1-5

    103 Building Standards Commission. . . . . . . . . . . . . . . . . . .1-5 104 Department of Housing and Community Development. . . . . . . . . . . . . . . . . .1-6 105 Division of the State Architect . . . . . . . . . . . . . . . . . . . . .1-6

    106 Office of Statewide Health Planning and Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

    CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

    201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

    202 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

    CHAPTER 3 GREEN BUILDING . . . . . . . . . . . . . . . . . . . . . . . . 3-3

    301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3

    302 Mixed Occupancy Buildings . . . . . . . . . . . . . . . . . . . . . . .3-4 303 Phased Projects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4 304 Voluntary Tiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4 305 CALGreen Tier 1 and CALGreen Tier 2 . . . . . . . . . . . . . .3-4

    306 Voluntary Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4

    CHAPTER 4 RESIDENTIAL MANDATORY MEASURES . . . . . . 4-3

    4.1 Planning and Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3 4.2 Energy Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-7 4.3 Water Efficiency and Conservation . . . . . . . . . . . . . . . . .4-9 4.4 Material Conservation and Resource Efficiency . . . . 4-11 4.5 Environmental Quality . . . . . . . . . . . . . . . . . . . . . . . . . . 4-13

    CHAPTER 5 NONRESIDENTIAL MANDATORY MEASURES . . 5-3

  • CALGreen § 18934.7. Medium relevance — show source text

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    APPENDIX A-2 2025 CALIFORNIA EXISTING BUILDING CODE

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    A GUIDELINES FOR THE SEISMIC RETROFIT OF EXISTING BUILDINGS

    User notes:

    About this appendix: Appendix A provides guidelines for upgrading the seismic-resistance capacity of different types of existing buildings. It is organized into separate chapters that deal with buildings of different types, including unreinforced masonry buildings, reinforced concrete and reinforced masonry wall buildings, and light-frame wood buildings.

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

    2025 (Group B) Code Development Cycle.

    CHAPTER A1

    SEISMIC STRENGTHENING PROVISIONS FOR UNREINFORCED MASONRY BEARING WALL BUILDINGS

    SECTION A100—APPLICATION

    A100.1 Vesting authority. When adopted by a state agency, the provisions of these regulations shall be enforced by the appropriate enforcing agency, but only to the extent of authority granted to such agency by the state legislature.

    Following is a list of the state agencies that adopt building standards, the specific scope of application of the agency responsible for enforcement, and the specific statutory authority of each agency to adopt and enforce such provisions of building standards of this code, unless otherwise stated.

    1. BSC—California Building Standards Commission.

    Application—Existing buildings as specified in Section A102 having at least one unreinforced masonry bearing wall, with the exception of buildings subject to building standards pursuant to Health and Safety Code, commencing with Section 17910.

    Enforcing Agency—State or local agency specified by the applicable provisions of the law.

    Authority Cited—Health and Safety Code Section 18934.7.

    Reference— Health and Safety Code Sections 18901 through 18949. 2. HCD 1—The Department of Housing and Community Development.

    Application—Hotels, motels, lodging houses, apartments, dwellings, employee housing and factory-built housing.

    Enforcing Agency—The local building department or the Department of Housing and Community Development.

    Authority Cited—Health and Safety Code Sections 17040, 17921, 17922 and 19990.

    Reference—Health and Safety Code Sections 17000 through 17060, 17910 through 17990, 19960 through 19997; and Govern- ment Code Section 12955.1.

    3. HCD 2—The Department of Housing and Community Development.

    Application—Permanent buildings and permanent accessory buildings or structures constructed within mobilehome parks and special occupancy parks.

    Enforcing Agency—The local building department or the Department of Housing and Community Development.

    Authority Cited—Health and Safety Code Sections 18300, 18620, 18640, 18865, 18873 and 18873.2.

    Reference—Health and Safety Code Sections 18200 through 18700 and 18860 through 18874.

    SECTION A101—PURPOSE

  • CALGreen § 1.8.2 Medium relevance — show source text

    SECTION 1.8.2—AUTHORITY AND ABBREVIATIONS

    1.8.2.1 General. The Department of Housing and Community Development is authorized by law to promulgate and adopt building standards and regulations for several types of building applications. The applications under the authority of the Department of Housing and Community Development are listed in Sections 1.8.2.1.1 through 1.8.2.1.3.

    Note: See the California Residential Code for detached one-and two-family dwellings and townhouses.

    1.8.2.1.1 Housing construction.

    Application— Hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilet or cooking facilities including accessory buildings, facilities and uses thereto. Sections of this code which pertain to applications listed in this section are identified using the abbreviation “HCD 1.”

    Enforcing agency— Local building department or the Department of Housing and Community Development.

    Authority cited— Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17922.15, 17926, 17927, 17928, 17958.12, 18938.3, 18944.11 and 19990; and Government Code Section 12955.1.

    Reference— Business and Professions Code Division 5, Health and Safety Code Sections 17000 through 17062.5, 17910 through 17995.5, 18200 through 18700, 18860 through 18874, 18938.6, 18941, 19890, 19891, 19892 and 19960 through 19997; Civil Code Sections 832, 1101.4, 1101.5 and 1954.201, 1954.202 and 5551; Government Code Sections 8698.4, 12955.1 and 12955.1.1. California Code of Regulations, Title 20, Sections 1605.1, 1605.3 and 1607.

    1.8.2.1.2 Housing accessibility.

    Application— Covered multifamily dwellings as defined in Chapter 2 of the California Building Code, including but not limited to, lodging houses, dormitories, timeshares, condominiums, shelters for homeless persons, congregate residences, apartments, dwellings, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilet or cooking facilities.

    Sections of this code identified by the abbreviation “HCD 1-AC” require specific accommodations for persons with disabilities as defined in Chapter 2 of the California Building Code. The application of such provisions shall be in conjunction with other requirements of the California Building Code, and apply only to newly constructed covered multifamily dwellings as defined in _Chapter 2 of the California Building Code.

  • CALGreen § 17062.5 Medium relevance — show source text

    Reference— Business and Professions Code Division 5, Health and Safety Code Sections 17000 through 17062.5, 17910 through 17995.5, 18200 through 18700, 18860 through 18874, 18938.6, 18941, 19890, 19891, 19892 and 19960 through 19997; Civil Code Sections 832, 1101.4, 1101.5 and 1954.201, 1954.202 and 5551; Government Code Sections 8698.4, 12955.1 and 12955.1.1. California Code of Regulations, Title 20, Sections 1605.1, 1605.3 and 1607.

    1.8.2.1.2 Housing accessibility.

    Application— Covered multifamily dwellings as defined in Chapter 2 of the California Building Code, including but not limited to, lodging houses, dormitories, timeshares, condominiums, shelters for homeless persons, congregate residences, apartments, dwellings, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilet or cooking facilities.

    Sections of this code identified by the abbreviation “HCD 1-AC” require specific accommodations for persons with disabilities as defined in Chapter 2 of the California Building Code. The application of such provisions shall be in conjunction with other requirements of the California Building Code, and apply only to newly constructed covered multifamily dwellings as defined in Chapter 2 of the California Building Code. “HCD 1-AC” applications include, but are not limited to, the following: 1. All newly constructed covered multifamily dwellings as defined in Chapter 2 of the California Building Code. 2. New common use areas as defined in Chapter 2 of the California Building Code, serving existing covered multifamily dwellings. 3. Additions to existing buildings, where the addition alone meets the definition of covered multifamily dwellings as defined in Chapter 2 of the California Building Code.

    2025 CALIFORNIA EXISTING BUILDING CODE 1-7

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

    ADMINISTRATION

    4. New common use areas serving new covered multifamily dwellings. 5. Where any portion of a building’s exterior is preserved, but the interior of the building is removed, including all structural portions of floors and ceilings, the building is considered a new building for determining the application of Chapter 11A of the California Building Code.

    “HCD 1-AC” building standards generally do not apply to public use areas or public accommodations such as hotels and motels, and public housing. Public use areas, public accommodations and public housing, as defined in Chapter 2 of the California Building Code, are subject to the Division of the State Architect (DSA-AC) in Chapter 11B of the California Building Code, and are referenced in Section 1.9.1.

    Enforcing agency— Local building department or the Department of Housing and Community Development.

  • CALGreen § 1.7 Medium relevance — show source text

    SECTION 1.7—CALIFORNIA DEPARTMENT OF PUBLIC HEALTH

    1.7.1 Specific scope of application of the agency responsible for enforcement, the enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

    California Department of Public Health

    Application— Organized camps, laboratory animal quarters, public swimming pools, radiation protection and producing facili- ties, commissaries serving mobile food preparation vehicles, wild animal quarantine facilities, shellfish facilities and food establishments.

    Enforcing agency— The California Department of Public Health and the local health agencies.

    Authority cited— Health and Safety Code Sections 1660, 18897.2, 110065, 112165, 113710, 114304, 115061, 116050, 121795 and 131200.

    Reference— Health and Safety Code Sections 1650, 1660, 18897.2, 18897.4, 18897.7, 100150, 110065, 113705, 113710, 114825, 114965, 115061, 116050, 116503, 112165, 121795 and 131200.

    1.7.2 Adopting agency identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym DPH.

    SECTION 1.8—DEPARTMENT OF HOUSING AND COMMUNITY DEVELOPMENT

    1.8.1 Purpose. The purpose of this code is to establish the minimum requirements necessary to protect the health, safety and general welfare of the occupants and the public by governing accessibility, erection, construction, reconstruction, enlargement, conversion, alteration, repair, moving, removal, demolition, occupancy, use, height, court, area, sanitation, ventilation, maintenance and safety to life and property from fire and other hazards attributed to the built environment.

    SECTION 1.8.2—AUTHORITY AND ABBREVIATIONS

    1.8.2.1 General. The Department of Housing and Community Development is authorized by law to promulgate and adopt building standards and regulations for several types of building applications. The applications under the authority of the Department of Hous- ing and Community Development are listed in Sections 1.8.2.1.1 through 1.8.2.1.3.

    Note: See the California Residential Code for detached one- and two-family dwellings and townhouses.

    1.8.2.1.1 Housing construction.

    Application— Hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping accommoda- tions with or without common toilet or cooking facilities including accessory buildings, facilities and uses thereto. Sections of this code which pertain to applications listed in this section are identified using the abbreviation “HCD 1.”

    Enforcing agency— Local building department or the Department of Housing and Community Development.

Frequently asked questions

Who enforces CALGreen for an apartment building?

Typically the local building department enforces CALGreen for apartment buildings within HCD’s scope; HCD itself is also an enforcing agency option under § 104.1. Confirm with your local jurisdiction.

Does CALGreen § 104.1 cover single‑family detached homes?

No. § 104.1 covers multi‑unit and other listed housing types. Detached one‑ and two‑family dwellings and townhouses are handled under the California Residential Code (see the note in the residential code).

If I want an alternate compliance path, who approves it?

Local building departments may approve alternates; the Department of Housing and Community Development may also approve alternates for HCD‑scoped buildings. Expect to submit substantiating tests or evidence.

Where do I find the actual mandatory green measures that apply to HCD projects?

See CHAPTER 4 — Residential Mandatory Measures in CALGreen and the Matrix Adoption Tables which identify measures adopted by HCD for covered occupancies.

Are graywater systems ever regulated by HCD under CALGreen?

Yes — CALGreen identifies graywater regulation and notes the Department of Water Resources and HCD in relevant matrix/adoption contexts; verify the specific graywater chapter/section and agency adoption.

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