Permits, financing, contractor vetting, design trade-offs, and cost math — every guide on this page is written for the person who owns the property, not the person who wants to build on it. Plain language, sourced to California statute, updated for 2026. The goal is that you walk into every conversation knowing more than whoever is trying to sell you something.
ADU housing explained — meanings across California, Oregon, Massachusetts. DADU, JADU, granny flat, casita defined. History 2016–2026 and real costs.
Read the guide EligibilityA 6-test eligibility framework for California ADUs: zoning, lot size, setbacks, parking, easements, utilities. Find out if your lot qualifies before you spend a dollar on design.
Read the guide Size & RulesCalifornia state law caps ADUs at 800, 1,200, or JADU 500 sqft depending on type. The rule stack, FAR, lot coverage, and second-story limits explained.
Read the guide Process GuideThe 8 chronological steps to build an ADU in California in 2026, with realistic timelines, decision points, and the costs that catch homeowners by surprise.
Read the guide PermitsThe ADU permit application package, the plan-check correction loop, and the five pitfalls that delay 80% of first-time California ADU permits.
Read the guide PermitsItemized LA ADU permit fees in 2026: plan check, building permit, MEP, school, surcharges. First-permit vs correction-round timelines from LADBS reporting.
Read the guide FinancingFirst-time ADU financing in California: the four primary loan paths, what they cost in 2026, and the one question that decides which one is right for you.
Read the guide InvestmentPutting $300K into a backyard ADU vs. a small LA rental condo. Side-by-side cap rate, leverage, tax, and risk math, calibrated June 2026.
Read the guide Ongoing CostsMonthly utility costs for a 600 sqft Los Angeles ADU in 2026: electricity, water, sewer, trash. Separate meter vs sub-meter math, panel upgrade triggers.
Read the guide Common MistakesThe five pre-construction decisions that wreck California ADU projects, what each one actually costs, and the homeowner-side fix for each.
Read the guide ContractorsThe homeowner-DIY playbook for vetting a California ADU contractor — CSLB lookup, BBB check, references, contract review — and where outside help belongs.
Read the guide ContractorsThe criteria and red flags California homeowners should run before signing an ADU contract in 2026. A practical filter, not a recommendation list.
Read the guide Design12 garage conversion design ideas for studios, 1BR ADUs, and home offices. Real trade-offs on cost, space, and permits — and when the design doesn’t pencil.
Read the guide Case StudyA real-numbers case study of converting a garage into a bedroom in California 2026. Cost, time, permit path, and when a bedroom beats an ADU.
Read the guideEvery guide in this library maps back to one of the four decision points that determine whether a California ADU project succeeds or fails before construction starts.
From eligibility to final inspection: the rules, timelines, and decision points for California ADU permits. Who approves what, correction-round risk, and how long it actually takes.
Loan paths, cost bands, permit fees, utility costs, and the ROI comparison against other investments. The math that tells you whether the project pencils before any money moves.
How to vet a California ADU contractor, the five disqualifying red flags, what to put in the contract, and what to do when things go wrong. The homeowner’s protection framework.
Garage conversions, detached builds, JADUs, and the design decisions that affect cost and appraised value. What works on which lot type, with real layout trade-offs and case studies.
A note on how ADUscale guides are written. ADUscale is a California build-side ADU partner: we help homeowners secure one of the state’s top contractors, expand that contractor’s capacity to take the project, and protect the budget with inspection-gated milestone payments — at the same price as going direct. Every guide is sourced to public statute, regulatory records, and verified data. The goal is a homeowner who can make a fully informed decision — including the decision not to proceed. Information in these guides is for planning and decision-support purposes and is not legal, engineering, or construction advice.
The guides in this library answer the how. The ADU Reality Check answers the whether — whether your California property qualifies, which of the five ADU types the lot supports, and whether the project math works at current construction costs. Two minutes, no design fees, no commitment. Sometimes the right answer, after the Reality Check, is that an ADU is not the right project for this lot, this budget, or this submarket. We say so clearly when it applies.
