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Author

Eli Cohen

Eli Cohen writes HomeAdd's homeowner guides about ADUs, home additions, garage conversions, planning, and construction.

Guides by Eli Cohen
ADU fundamentals

What Is an ADU? Types, Rules & Uses Explained

A plain-language explanation of accessory dwelling units — what legally counts as one, the five types, what a JADU is, and how homeowners actually use them.

Permits & process

How Big Can an ADU Be in California? Size & Height Rules

What state law says about maximum ADU square footage, the 800 sq ft protection, height allowances, and JADU limits — and why your city still matters.

Design & layout

ADU Floor Plans & Layouts: What Works at Each Size

How ADU layouts change from a studio to a two-bedroom — circulation, kitchen placement, storage, daylight, and the plan decisions that cost money later.

Decision guide

How Much Value Does an ADU Add to Your Home?

How appraisers and buyers treat an ADU, why permitted square footage matters, and the honest limits of any value estimate before an appraisal.

Cost & budgeting

ADU Rental Income in California: What to Plan For

How to research realistic ADU rent, the costs that come out of it, short- vs. long-term rules, and how lenders and taxes treat the income.

Cost & budgeting

How Much Does It Cost to Build an ADU in California?

What an ADU actually costs to build in California — hard costs, soft costs, utilities, and the site conditions that move the number most.

Cost & budgeting

Home Addition Cost: What Actually Shapes the Number

A plain-language breakdown of home addition cost — square footage, structure, utilities, finishes, professional fees, and contingency.

Cost & budgeting

Second-Story Addition Cost in California (2026)

Why building up costs more per square foot than building out, what the structural work involves, and how to budget a second-story addition.

Cost & budgeting

Cost of Adding a Bedroom to a House in California

What drives the cost of adding a bedroom, how a bedroom-plus-bath compares, and the code requirements a room must meet to count as a bedroom.

Cost & budgeting

How to Pay for a Home Addition or ADU

The common ways California homeowners fund an addition or ADU — equity, renovation loans, construction loans, cash — and the trade-offs of each.

Timeline

How Long Does a Home Addition Take?

A realistic calendar for a California home addition — design, engineering, plan check, construction, inspections — and what stretches each stage.

Decision guide

Can I Add a Bedroom to My House? Permits, Cost & Feasibility in California

What makes a bedroom addition feasible, when you need a permit, how it differs from an ADU, and the budget factors that shape the project.

Cost & budgeting

Room Addition Cost in Los Angeles: 2026 Planning Guide

Preliminary planning ranges for a Los Angeles room addition, what drives cost up or down, and how a written proposal replaces any guess.

Permits & process

Do I Need a Permit for a Kitchen Remodel in California?

When a kitchen refresh needs no permit, when a permit is required, and the inspections that apply when walls, plumbing, or electrical move.

Conversions

Can I Convert My Garage Into an ADU in California?

The feasibility checklist for a garage-to-ADU conversion — structure, setbacks, utilities, parking, and the city-specific rules that decide it.

Decision guide

ADU vs. Second-Story Addition: Which Adds More Value?

Compare a backyard ADU with building up — cost, zoning, disruption, rental income, and which option fits your lot and long-term plans.

Decision guide

Home Addition vs. Moving: Which Makes More Financial Sense?

How to compare the true cost of adding on with the cost of selling, buying, and moving — including the less obvious numbers.

Design ideas · Small spaces

Creative ADU Ideas for Small Spaces and Tight Lots

Layout, storage, daylight, and siting ideas that make a 350–600 sq ft ADU live larger — plus the setback and utility realities that shape a small-lot design.

Cost & budgeting · Orange County

ADU Cost in Orange County: 2026 Planning Ranges

Preliminary planning ranges by ADU type for OC homeowners, plus the lot, HOA, coastal, and city-fee factors that move an Orange County budget.

Permits & process · Orange County

ADU Permit Timeline in Orange County (2026)

How ADU permitting works across Orange County's cities — ministerial review, the 60-day rule, HOA and coastal tracks, and what actually slows approvals.

Conversions · Orange County

Garage Conversion Permits in Orange County

Who reviews an OC garage conversion, the state rules that protect conversions (including parking), coastal-zone notes, and the submittal path in order.

Cost & budgeting · Ventura County

ADU Cost in Ventura County: 2026 Planning Ranges

Preliminary planning ranges by ADU type for Ventura County, plus the hillside, fire-zone, oak-tree, and septic factors that move a local budget.

Permits & process · Ventura County

ADU Permits in Ventura County: City vs. County

City departments vs. Ventura County RMA, oak and fire-hazard review, hillside and septic conditions, and the ADU approval sequence step by step.

Permits & process

Home Addition Permits in Los Angeles: A 2026 Homeowner's Guide

How addition permits work in the City of Los Angeles — zoning checks, regular vs. counter plan check, HPOZ review, 2025 Energy Code compliance, and inspections.

Feasibility

Can I Build an ADU in My Backyard in Los Angeles? A 2026 Feasibility Checklist

A practical checklist for Los Angeles backyard ADUs: jurisdiction, lot configuration, setbacks, overlays, utilities, access, and which ADU type fits your property.

Permits & process

ADU Permit Timeline in Los Angeles: What Homeowners Should Expect in 2026

The phases every Los Angeles ADU moves through — feasibility, design, submittal, plan check, issuance, inspections — and what actually stretches the schedule.

ADU fundamentals

ADU Utilities Explained: Sewer, Water, Electrical & Gas Planning in Los Angeles

Sewer laterals, water service, electrical capacity, gas versus all-electric, and metering — what has to be investigated on your parcel before design gets locked.

Cost & budgeting

How Much Does an ADU Cost in Los Angeles, Orange & Ventura Counties?

Preliminary planning ranges by ADU type, the seven factors that move a budget, hard vs. soft costs, and how to compare two proposals fairly.

Conversions

Garage Conversion to ADU: A California Homeowner's Guide

Feasibility on an existing garage, the habitability upgrades code requires, parking rules under state law, permit paths, and the mistakes that stall plan check.

Decision guide

ADU vs. Room Addition: Which Is Right for Your Home?

A side-by-side comparison of cost, permits, rental potential, yard impact, and livability — plus how your lot should influence the decision.

Decision guide

Attached vs. Detached ADU: Cost, Privacy, Design & Property Considerations

Sharing a wall with the main house versus standing alone: how each option changes construction cost, privacy, utilities, yard use, and long-term flexibility.

Timeline

How Long Does It Take to Build an ADU in Los Angeles? Design to Final Inspection

The full project calendar for a Los Angeles ADU — feasibility, design, permitting, construction, inspections, closeout — and what compresses or stretches each stage.

Permits & process

ADU Setback Requirements in California: A Homeowner's 2026 Guide

How ADU setbacks work in California, why the answer is parcel-specific, and how to read your own lot using the March 2026 HCD ADU Handbook as the reference.

Cost & budgeting

How Much Does a 500 Sq. Ft. ADU Cost in Los Angeles? 2026 Planning Guide

What actually moves the budget on a 500-square-foot Los Angeles ADU: type, site conditions, utilities, finishes, soft costs, and how to compare two proposals.

Decision guide

Detached ADU vs. Garage Conversion in Los Angeles: Which Is Better for Your Property?

How a new detached unit and a converted garage differ on budget, yard space, design freedom, unknowns, rental appeal, and schedule — and how your lot decides it.

Feature guide · July 2026

California ADU Guide for 2026: Planning, Permits, Costs & Construction

How detached, attached, conversion ADUs, and JADUs work in California — feasibility, permits, Title 24, utilities, budgets, and the questions to ask a contractor.