Development & building
Zoning, ADUs, changes of use, building systems, life safety, and what an inspector checks.
Try an example question about Development & buildingRead the laws on Development & buildingCalifornia building codes & real estate regulations
Know which rules apply to your property and project.
Research the original sources. Understand how requirements fit together. Check the conditions and exceptions that matter to your work.
California local & state sources · Selected federal authorities
Your first AI answer is free · 7-day free trial after that. View pricing
Start with your work
What are you working through?
From a construction detail to a sale, a lease, an HOA dispute, an auction, or a tax bill — start with the question you need to resolve.
Buying & selling
Disclosure obligations, property constraints, and questions to resolve before closing.
Try an example question about Buying & sellingRead the laws on Buying & sellingRenting & eviction
Rent increases, deposits, evictions, tenant protections, and maintenance obligations.
Try an example question about Renting & evictionRead the laws on Renting & evictionOwning & HOAs
Association authority, assessments, rental restrictions, records, and owner rights.
Try an example question about Owning & HOAsRead the laws on Owning & HOAsForeclosure & auctions
Notices of default and sale, trustee-sale bidding, and tenants after a sale.
Try an example question about Foreclosure & auctionsRead the laws on Foreclosure & auctionsProperty taxes
Change of ownership, reassessment, Prop 19 transfers, and tax-defaulted property sales.
Try an example question about Property taxesRead the laws on Property taxesSource coverage varies by topic and jurisdiction. Check coverage.
Follow the requirement to its source
One question can cross several rulebooks.
Set the context
Location, use, existing conditions, and the relevant date help frame which requirements to investigate.
Compare the layers
Review relevant local, state, and federal sources alongside building, housing, and property rules.
Check the original text
Follow citations, read the exceptions, and distinguish supported findings from facts that still need confirmation.
Example reviews
Different work. The same need for evidence.
Example review outlines show how to frame a question. They are not completed analyses or legal conclusions. Read reviews with original sources.
Design & inspection
A small shed. Several rules to check.
- Establish the facts
- Location, dimensions, use, and distance to the property line.
- Read the rules together
- Compare the permit exemption with local zoning and the applicable fire-separation provisions.
- Resolve what matters
- Identify which requirements remain relevant even if a permit exemption applies.
Permits & change of use
A new use in an existing building.
- Establish the facts
- Existing occupancy, proposed care services, occupant count, and building layout.
- Read the rules together
- Read the occupancy classification, sprinkler provisions, and local amendments together.
- Resolve what matters
- Separate potential exceptions from facts and approvals that still need confirmation.
Property & community
A rental restriction under review.
- Establish the facts
- Jurisdiction, the exact restriction, relevant dates, and governing documents.
- Read the rules together
- Compare the restriction with applicable state statutes and any relevant local rules.
- Resolve what matters
- Identify missing documents and conditions before reaching an enforcement conclusion.
For the people making property decisions.
Across the drawing board, the job site, the closing table, the HOA board, the auction, and the tax roll.
Architects
Design constraints and code exceptions.
Engineers
Structural, fire, and building-system requirements.
Inspectors
Inspection criteria and the source behind them.
Builders & contractors
Installation details and construction requirements.
Developers & permit consultants
Allowed uses, approvals, and submittals.
Agents & brokers
Disclosure and transaction research.
Property managers
Rent, eviction, and maintenance obligations.
HOA managers
Association authority, assessments, and owner rights.
Attorneys
Applicable provisions and how they interact.
Tax professionals
Reassessment, exclusions, and transfer taxes.
Auction buyers
Trustee-sale and tax-sale rules before you bid.
Homeowners
Improvements, ownership, and rental questions.
540
California cities & counties covered
1,199
Codes & ordinances in the library
1.2 million+
Code sections, verbatim and cited
Explore source coverage for your topic and jurisdiction.
Browse California codes & regulations
Code Library
The verbatim enacted text of 1,199 codes, ordinances, and statutes, section by section.
Title 24 Building Codes
All 13 parts of the California Building Standards Code, explained in plain English.
Housing & Tenant Laws
Rent control, evictions, ADU law, and the statewide housing statutes.
Zoning by City
Zoning and planning-code guides for 480+ California cities.
Zoning by County
Regulation guides for all 58 California counties.
ADU Rules by City
The state-law baseline plus each city's local ADU requirements, compared side by side.
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Frequently asked questions
What is GoCodebook?
GoCodebook is an AI research assistant for building codes and real estate regulations. Research California property and project questions across design, construction, permits, buying and selling, rentals, HOA rules, foreclosure and auctions, and property tax, with citations you can check against the original text.
Which codes and cities does GoCodebook cover?
Title 24, the California Building Standards Code: 12 of its 13 parts in the 2025 edition, with the Electrical Code in its 2022 edition. Also the statewide housing laws — including ADU law, SB 9, and rent control — and local zoning for 540 California cities and counties. The Code Library holds the verbatim text of 1,199 codes, ordinances and statutes, more than 1.2 million sections. Local coverage is California-focused. The library also includes California real estate statutes and selected federal housing and real estate authorities; coverage varies by topic. See full coverage.
Who is GoCodebook for?
Architects, engineers, inspectors, builders and contractors, permit consultants, developers, agents and brokers, property managers, HOA managers, attorneys, tax professionals, auction buyers, public agencies, and homeowners. Start with the question you need to resolve; your role does not limit which topics you can research.
How does GoCodebook handle overlapping regulations?
Ask it to compare the relevant local, state, and federal requirements, along with the building use, project scope, and applicable date. Review each source and its exceptions: different requirements may apply together, and missing property facts can change the analysis.
Is GoCodebook free to use?
Reading the Code Library is free with no sign-up — every document, in full. Your first AI answer is free; after that, AI answers and library search run on credits. Starter is $15/month for 100 credits and starts with a 7-day free trial (card required). See pricing.
How accurate are GoCodebook's answers?
GoCodebook retrieves source text and provides citations for you to review. Check the cited language, applicable edition, jurisdiction, and exceptions against your facts. AI can make mistakes or miss a relevant requirement — see the methodology for how answers are grounded and what the review dates mean.
Does GoCodebook replace a permit review or professional advice?
GoCodebook supports research; it does not provide an official approval or replace legal, tax, engineering, or other professional advice. Use the cited sources to support your review, and confirm project-specific determinations with the relevant authority or qualified professional.