# GoCodebook

> GoCodebook is an AI research assistant for building codes and real estate regulations, with original sources to check. Local and state coverage focuses on California, alongside selected federal authorities.

Research tasks include design, construction, inspection, permits, development, buying and selling, rentals and evictions, HOAs, foreclosure and auctions (trustee sales, tax-defaulted property), and property tax. Built for architects, engineers, inspectors, builders, developers, agents and brokers, property managers, HOA managers, attorneys, tax professionals, auction buyers, and homeowners. Check source coverage, relevant dates, applicability, and exceptions. AI can miss relevant provisions or misapply a source; answers support professional review and are not official determinations.

## Product
- [Home](https://gocodebook.com/): Research building codes and real estate regulations.
- [Features](https://gocodebook.com/features): Source-based research, applicability, and review of overlapping rules.
- [Pricing](https://gocodebook.com/pricing): Library reading is free. The first AI answer is free; after that AI answers and search use credits, with a 7-day free Starter trial.
- [Use cases](https://gocodebook.com/use-cases): Illustrative scenarios for design, inspection, transactions, rentals, HOA, foreclosure and auctions, and property tax.
- [Coverage](https://gocodebook.com/coverage): Source coverage by jurisdiction and subject, with limitations.
- [Compare](https://gocodebook.com/compare): Workflow comparisons with official product sources.
- [Local ordinance API](https://gocodebook.com/developers): REST API for legal, real estate and compliance software that searches the local ordinances (municipal, zoning and planning codes) of 540 California cities and counties — zoning, rentals, business licensing, permits and more — and returns JSON with citations, verbatim excerpts and links. Free keyless sample; $0.30 a search with the AI overview included, from a prepaid balance. OpenAPI: https://gocodebook.com/api/v1/openapi.json; interactive reference: https://gocodebook.com/developers/reference.
- [API topics covered](https://gocodebook.com/developers/topics): Local ordinance topics by category (land use, rentals, business licensing, regulated businesses, public order) with how many California cities and counties' codes cover each.
- [Local ordinance API for legal AI](https://gocodebook.com/developers/use-cases/legal-ai): Why legal AI lacks city and county law and how cited, verbatim ordinance search fills it.
- [Local ordinance sources compared](https://gocodebook.com/developers/compare): GoCodebook API vs LexisNexis, Westlaw, Free Law Project, code publishers and zoning data APIs, with sources.
- [MCP server](https://gocodebook.com/mcp): Use the code library from Claude, ChatGPT and other MCP clients.
- [GoCodebook in Claude](https://gocodebook.com/mcp/claude): Add GoCodebook to Claude as a custom connector.
- [GoCodebook in ChatGPT](https://gocodebook.com/mcp/chatgpt): Add GoCodebook to ChatGPT as a custom MCP app in developer mode.
- [Get started](https://gocodebook.com/get-started): Free property feasibility survey — no signup required.
- [Frequently asked questions](https://gocodebook.com/questions): Recurring California code questions, answered with citations to the controlling sections.
- [Developer guides](https://gocodebook.com/guides): Practical guides to California multifamily development and underwriting — density bonus, streamlined approvals, rent control, demolition rules, fees, CEQA, building codes, land division, due diligence, and LIHTC financing, each citing the verbatim law in the Code Library.
- [Development glossary](https://gocodebook.com/guides/glossary): Plain-English definitions of California development and underwriting terms, each linked to the governing statute or code.

## California Building Standards Code (Title 24, 2025 edition)
- [Title 24 overview](https://gocodebook.com/us/california/building-codes): All 13 parts of the California Building Standards Code.
- [California Administrative Code (CAC) — Title 24 Part 1](https://gocodebook.com/us/california/california-administrative-code): Administrative regulations and procedures that govern how the California Building Standards Code is adopted and enforced.
- [California Building Code (CBC) — Title 24 Part 2](https://gocodebook.com/us/california/california-building-code): Structural, fire, accessibility and occupancy requirements for commercial and multifamily buildings.
- [California Residential Code (CRC) — Title 24 Part 2.5](https://gocodebook.com/us/california/california-residential-code): Construction standards for one- and two-family dwellings and townhouses up to three stories.
- [California Electrical Code (CEC) — Title 24 Part 3](https://gocodebook.com/us/california/california-electrical-code): Electrical installation, wiring and safety requirements based on the National Electrical Code.
- [California Mechanical Code (CMC) — Title 24 Part 4](https://gocodebook.com/us/california/california-mechanical-code): HVAC, ventilation, exhaust and mechanical system requirements.
- [California Plumbing Code (CPC) — Title 24 Part 5](https://gocodebook.com/us/california/california-plumbing-code): Plumbing, drainage, venting and water-supply requirements.
- [California Energy Code — Title 24 Part 6](https://gocodebook.com/us/california/california-energy-code): Energy-efficiency standards for residential and nonresidential buildings (Title 24, Part 6).
- [California Wildland-Urban Interface Code (CWUIC) — Title 24 Part 7](https://gocodebook.com/us/california/california-wildland-urban-interface-code): Fire-resistant construction requirements for buildings in wildfire-prone (WUI) areas.
- [California Historical Building Code (CHBC) — Title 24 Part 8](https://gocodebook.com/us/california/california-historical-building-code): Alternative standards that preserve qualified historic buildings while protecting safety.
- [California Fire Code (CFC) — Title 24 Part 9](https://gocodebook.com/us/california/california-fire-code): Fire prevention, protection systems and life-safety requirements.
- [California Existing Building Code (CEBC) — Title 24 Part 10](https://gocodebook.com/us/california/california-existing-building-code): Repair, alteration, addition and change-of-occupancy provisions for existing buildings.
- [California Green Building Standards Code (CALGreen) — Title 24 Part 11](https://gocodebook.com/us/california/california-green-building-standards-code): Green building, water-efficiency and sustainability requirements.
- [California Referenced Standards Code (CRSC) — Title 24 Part 12](https://gocodebook.com/us/california/california-referenced-standards-code): The referenced standards adopted into and enforced under Title 24.

## California housing & tenant law
- [Housing & tenant law overview](https://gocodebook.com/us/california/housing-laws): Rent control, evictions, and ADU law in California.
- [California Rent Control](https://gocodebook.com/us/california/california-rent-control): How rent control works in California — statewide caps, local ordinances, and what's exempt.
- [AB 1482 — Tenant Protection Act of 2019](https://gocodebook.com/us/california/ab-1482-tenant-protection-act): Statewide rent caps and just-cause eviction protections for most California rentals.
- [Costa-Hawkins Rental Housing Act](https://gocodebook.com/us/california/costa-hawkins-rental-housing-act): The state law that limits local rent control on newer units and vacant apartments.
- [Ellis Act](https://gocodebook.com/us/california/ellis-act): The law letting landlords exit the rental business and withdraw units from the market.
- [SB 567 — Homelessness Prevention Act](https://gocodebook.com/us/california/sb-567-homelessness-prevention-act): The 2024 amendments that tightened AB 1482's just-cause and rent-cap rules.
- [Just Cause Eviction (Civil Code § 1946.2)](https://gocodebook.com/us/california/just-cause-eviction): When a landlord must have a valid reason to end a tenancy in California.
- [Statewide Rent Cap (Civil Code § 1947.12)](https://gocodebook.com/us/california/statewide-rent-cap): How much rent can legally increase each year under California's statewide cap.
- [Security Deposits (Civil Code § 1950.5)](https://gocodebook.com/us/california/security-deposit-law): How much a landlord may collect, what it may be used for, and the deadline and itemization for returning it.
- [Habitability & Repair-and-Deduct (§§ 1941–1942)](https://gocodebook.com/us/california/habitability-and-repair-and-deduct): What makes a rental untenantable, the locks a landlord must provide, and when a tenant may repair and deduct.
- [Retaliatory Eviction (Civil Code § 1942.5)](https://gocodebook.com/us/california/retaliatory-eviction): The protection against being evicted or penalized for complaining about conditions or exercising a tenant right.
- [Landlord Entry & Notice (Civil Code § 1954)](https://gocodebook.com/us/california/landlord-entry-notice): When a landlord may enter a rental, the notice it takes, and the exceptions.
- [Breaking a Lease — Damages (§§ 1951.2, 1951.4)](https://gocodebook.com/us/california/lease-breach-damages): What a landlord may recover when a tenant leaves early, and the duty to mitigate that limits it.
- [Tenant Harassment, Lockouts & Owner Disclosure](https://gocodebook.com/us/california/tenant-harassment-and-lockouts): The conduct a landlord may never use to push a tenant out, and the owner information every tenant is owed.
- [California Fair Housing Law (FEHA & 2 CCR)](https://gocodebook.com/us/california/california-fair-housing-law): Who and what the Fair Employment and Housing Act reaches, and how intentional discrimination and discriminatory effect are proved.
- [Source of Income Discrimination (Section 8)](https://gocodebook.com/us/california/source-of-income-discrimination): Why a voucher is income, what a landlord may verify, and how income screens must treat the tenant's share of rent.
- [Assistance Animals in Rental Housing](https://gocodebook.com/us/california/assistance-animals-rental-housing): Service and support animals — what a housing provider may ask, may not charge, and when it may say no.
- [Reasonable Accommodations & Modifications](https://gocodebook.com/us/california/reasonable-accommodation-housing): The interactive process, the documentation a provider may request, the grounds for denial, and who pays for a physical change.
- [Criminal History in Tenant Screening](https://gocodebook.com/us/california/criminal-history-tenant-screening): What criminal history a housing provider may consider, the individualized assessment it owes, and what it may never use.
- [HOA Fines & Hearings](https://gocodebook.com/us/california/hoa-fines-and-hearings): The $100 cap on HOA fines, the written notice and hearing a board owes before disciplining a member, and the dispute steps that follow.
- [Inheriting a House Without Probate](https://gocodebook.com/us/california/inheriting-a-house-without-probate): The ways a California house passes at death without a full probate — trust, transfer-on-death deed, surviving spouse, and the small-estate court paths.
- [HOA Dues & Special Assessments](https://gocodebook.com/us/california/hoa-assessment-increases): How much a board may raise regular dues or levy a special assessment without a member vote, and the emergency exceptions.
- [HOA Records Inspection](https://gocodebook.com/us/california/hoa-records-inspection): Which association records members may inspect and copy, how fast the association must produce them, and what it may withhold.
- [HOA Elections](https://gocodebook.com/us/california/hoa-elections): Secret ballots, nomination notice, inspectors of elections, and the rules for counting votes in a California HOA.
- [HOA Dispute Resolution](https://gocodebook.com/us/california/hoa-dispute-resolution): Internal dispute resolution, the mediation step before a lawsuit, and who pays attorney's fees in an HOA dispute.
- [Late HOA Dues, Liens & Foreclosure](https://gocodebook.com/us/california/hoa-delinquent-assessments-and-foreclosure): Late charges and interest on unpaid dues, the notice before a lien, and when an HOA may foreclose.
- [What an HOA Cannot Ban](https://gocodebook.com/us/california/what-an-hoa-cannot-ban): Solar panels, EV chargers, renting, pets, ADUs, flags and drought-tolerant yards — the limits California puts on HOA rules.
- [HOA Budgets & Reserves](https://gocodebook.com/us/california/hoa-budget-and-reserves): The annual budget report, reserve studies, balcony inspections, and the board's duties over association money.
- [HOA Documents for Home Buyers](https://gocodebook.com/us/california/hoa-documents-for-buyers): The HOA documents a seller must give a buyer, how fast the association must provide them, and what it may charge.
- [Transfer on Death Deeds](https://gocodebook.com/us/california/transfer-on-death-deed): How a California TOD deed is signed, recorded and revoked, what it transfers at death, and what the beneficiary must do next.
- [The Primary-Residence Petition](https://gocodebook.com/us/california/primary-residence-petition): The court petition that passes a decedent's home worth up to $750,000 without a full probate.
- [Small-Estate Affidavit for Real Property](https://gocodebook.com/us/california/small-estate-affidavit-real-property): The six-month affidavit that transfers low-value real property without probate, and the liability that comes with it.
- [Inheriting a House Held in a Trust](https://gocodebook.com/us/california/inherited-house-in-a-trust): The successor trustee's notice, the deadline to contest the trust, accountings, and the assessor filing.
- [Selling a House in Probate](https://gocodebook.com/us/california/selling-an-inherited-house): Independent administration and the notice of proposed action, or a court-confirmed sale with overbids.
- [Property Passing to a Surviving Spouse](https://gocodebook.com/us/california/surviving-spouse-property): When a home passes to a surviving spouse without administration, the spousal property petition, and the spouse's liability for debts.
- [Who Inherits Without a Will](https://gocodebook.com/us/california/who-inherits-without-a-will): California's intestacy order — the surviving spouse's share, then children, parents, siblings and more distant relatives.
- [California ADU Laws](https://gocodebook.com/us/california/california-adu-laws): State ADU and JADU rules that override many local restrictions on accessory dwelling units.

## Compare GoCodebook
- [GoCodebook vs ChatGPT](https://gocodebook.com/compare/chatgpt)
- [GoCodebook vs Claude](https://gocodebook.com/compare/claude)
- [GoCodebook vs UpCodes](https://gocodebook.com/compare/upcodes)
- [GoCodebook vs International Code Council (ICC)](https://gocodebook.com/compare/icc)
- [GoCodebook vs Municode](https://gocodebook.com/compare/municode)
- [GoCodebook vs eCode360](https://gocodebook.com/compare/ecode360)
- [GoCodebook vs American Legal Publishing](https://gocodebook.com/compare/american-legal)
- [GoCodebook vs General Code](https://gocodebook.com/compare/general-code)
- [GoCodebook vs Regrid](https://gocodebook.com/compare/regrid)
- [GoCodebook vs ArcGIS (Esri)](https://gocodebook.com/compare/arcgis)
- [GoCodebook vs PermitFlow](https://gocodebook.com/compare/permitflow)
- [GoCodebook vs Gridics](https://gocodebook.com/compare/gridics)
- [GoCodebook vs Symbium](https://gocodebook.com/compare/symbium)
- [GoCodebook vs Zoneomics & National Zoning Atlas](https://gocodebook.com/compare/zoning-data-platforms)

## California ADU data
- [ADU rules by city](https://gocodebook.com/us/california/adu-rules-by-city): Size limits, setbacks, parking, owner-occupancy and timelines compared across California cities.
- [State of California ADU Rules report](https://gocodebook.com/us/california/adu-rules-report): Aggregate statistics on where cities diverge from the state ADU floor — computed from the dataset, citable with attribution.

## Local zoning by jurisdiction
- [All California jurisdictions](https://gocodebook.com/us/california/cities): Zoning, planning, and building-code guides for 480+ California cities and 58 counties.

## California real estate law by topic
The Code Library's six topic shelves: the verbatim statutes, regulations and local codes for each stage of a property's life.
- [Development & building: zoning, codes and approvals](https://gocodebook.com/library/us/ca/topics/development-and-building): What can be built and how: the Title 24 building codes, every city and county zoning code, and the state planning, environmental and development-finance law above them.
- [Buying & selling: brokerage and disclosure](https://gocodebook.com/library/us/ca/topics/buying-and-selling): The rules for the people who carry a sale: real estate licensing, broker supervision, trust funds and the Real Estate Commissioner's regulations.
- [Renting & eviction: tenancy and fair housing](https://gocodebook.com/library/us/ca/topics/renting-and-eviction): Rent caps, just cause, deposits, repairs and entry, the eviction lawsuit itself, and the fair-housing rules every rental decision is read against.
- [Owning & HOAs: inheritance, insurance and trusts](https://gocodebook.com/library/us/ca/topics/owning-and-hoas): What comes with holding a property: HOA disclosures, assessments and disputes, loan servicing, homeowners insurance, trusts, and passing a home on at death.
- [Foreclosure & auctions: trustee, tax and court sales](https://gocodebook.com/library/us/ca/topics/foreclosure-and-auctions): The law and official process for trustee's sales, tax-defaulted property, judgment enforcement, probate sales and bankruptcy.
- [Property taxes: reassessment and transfer taxes](https://gocodebook.com/library/us/ca/topics/property-taxes): Find property assessment, reassessment, exemptions, tax bills, appeals and transfer taxes by the task you need to complete.

## Code Library — verbatim code text
- [Code Library](https://gocodebook.com/library): The verbatim enacted text of California municipal codes, Title 24, and state real estate statutes and regulations — every title, chapter, and section, with stable citations.
- [California Code Library](https://gocodebook.com/library/us/ca): 500+ city and county codes plus state real estate, tax, foreclosure and housing statutes, organized by jurisdiction, chapter, and section.

## Company
- [About](https://gocodebook.com/about): Who builds GoCodebook and why.
- [Methodology](https://gocodebook.com/methodology): Where the code text comes from, how AI answers are grounded, and what the review dates mean.
- [Blog](https://gocodebook.com/blog): Guides on zoning, permits, ADUs, and California code updates.
- [Blog RSS feed](https://gocodebook.com/rss.xml)
- [Contact](https://gocodebook.com/contact): Get in touch with the GoCodebook team.
- [Privacy Policy](https://gocodebook.com/privacy)
- [Terms of Service](https://gocodebook.com/terms)

## Optional
- [Full jurisdiction index](https://gocodebook.com/llms-full.txt): Machine-readable list of every California city and county page, plus the verbatim Code Library documents.