Luxury Design & Construction · Los Angeles

ADU Construction in Los Angeles

ADU construction across Los Angeles by one licensed team: garage conversions and new detached backyard homes, permitted for your city and built like real residences, because that is what they are.

5.0 ★★★★★ on GoogleLicensed & Insured · CSLB #10450302-Year Written Warranty
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ADU Construction

Your Backyard Has Room for a Second Home

Most Los Angeles backyards can legally fit a second, smaller home. Maybe yours becomes a rental. Maybe it houses your parents, or a kid saving for their own place, or the office you can never carve out of the main house. As a licensed ADU contractor in Los Angeles, we build both kinds: garages turned into real apartments, and brand-new detached units from the slab up.

One team runs the whole job. We design it, pull the permits, and build it with our own crews under CSLB License #1045030. You approve a fixed, itemized price before construction starts, and most of our ADUs finish in 3 to 5 months. The first step costs nothing: we walk your lot, tell you honestly what fits, and give you a real number.

What We Do

ADU Construction Services in Los Angeles

01

Detached ADU Construction

A ground-up home in the backyard, from fresh foundation to final coat of paint. Its own walls, its own kitchen and bath, its own front door. A complete residence, not an addition.

02

Garage Conversions

We turn underused garages into bright, finished apartments. Real insulation, proper ventilation, new flooring and drywall, so nothing about the space says garage anymore.

03

Attached ADUs

Additions that connect to your existing home while functioning as an independent unit, planned so both spaces keep their privacy.

04

ADU Design and Planning

Layouts, finishes, and site planning shaped around how the unit will actually be used, whether that is a long-term rental or a home for family.

05

Permits and Approvals

We prepare and pull your ADU permits and manage the inspection process, so approvals stay on our plate instead of yours.

06

Foundations and Framing

Foundation and framing never make the photo gallery, but every wall, pipe, and tile stands on them. We engineer this stage, build it to plan, and get it inspected before anything covers it up.

07

Full Kitchens and Baths

Every ADU we build can include a complete kitchen and full bathroom, finished to the same standard as the main house.

08

Electrical and Plumbing

New electrical and plumbing runs sized for independent living, installed cleanly and inspected at every required stage.

09

HVAC and Insulation

Efficient heating and cooling paired with proper insulation, so the unit stays comfortable year-round and affordable to run.

10

Interior Finishes

Cabinetry, tile, paint, lighting, and trim selected and installed with the same care we bring to high-end main residences.

11

Rental-Ready ADUs

Building a rental? We plan for tenants: durable finishes, surfaces that clean up fast, and a layout that shows well and holds up between leases.

12

Multigenerational Living Suites

Units planned for parents, in-laws, or adult kids: a full kitchen, their own front door, and family just across the yard when it matters.

Recent Work

A Recent ADU Build in Los Angeles

A recent detached ADU we built for a Los Angeles homeowner, photographed at completion.

Backyard adu construction 1 in Sherman Oaks by Athenian Builders
ADU contractor Sherman Oaks

Client Reviews

What Homeowners Say

5.0 ★★★★★ rating on Google
E
Eugenios SlidisGoogle review
★★★★★

I don’t usually leave reviews, but these guys did a solid job on our bathroom remodel in Los Angeles. Easy to work with and very professional. Good communication, fair pricing, and the final result came out really nice for our AirBnb investment.

T
Tal BenGoogle review
★★★★★

From the first consultation to the final walkthrough, Athenian Builders Group was fantastic. They remodeled our kitchen with custom cabinets, new countertops, and lighting, and it completely changed the space. Their professionalism and craftsmanship were impressive throughout the project.

R
Rachel B.Google review
★★★★★

My husband and I hired them for our bathroom remodel. They were very easy to work with and kind to answer all our questions patiently. They gave us a 3D design of our bathroom before they start and we loved how they brought our vision exactly how we wanted. Couldn’t be more satisfied.

Is It Time?

Why Homeowners Build ADUs

Earn Rental Income

Los Angeles never has enough housing. A permitted ADU puts a rentable unit on land you already own, working for you month after month.

One rule worth knowing early: a full ADU can be rented long-term with no requirement that you live on the property. A junior ADU is different, because state law requires the owner to live on site and limits short-term rentals. We confirm which rules apply to your lot during design.

House Family Comfortably

Give relatives a real home of their own, with a kitchen, bath, and front door, right on your property.

Create a Home Office or Studio

An office across the yard gives you a real workday: quiet, a door that closes, and a commute measured in steps.

Keep Aging Parents Close

Parents stay independent in their own space while family remains seconds away when it matters.

Give Adult Kids a Place of Their Own

Adult children get privacy and a real front door while they save toward their next step.

Increase Property Value

Permitted square footage is what appraisers and buyers actually pay for, and an ADU adds a whole extra unit of it.

Put Unused Space to Work

That garage full of boxes or empty stretch of yard can become the most productive square footage you own.

Host Guests in Comfort

A flexible guest suite means visitors get their own space and you keep yours.

The Process

How Your ADU Comes Together

One accountable team from the first walkthrough to the day you hand over the keys, no vendor hand-offs, no finger-pointing.

1

Consult & Feasibility

A free on-site visit and an honest read on what your lot can support.

2

Design & Permits

We shape the layout and pull your ADU permits.

3

Construction

Our own crews build it, foundation to finishes, on a firm schedule.

4

Walkthrough & Move-In

Room-by-room walkthrough, then a finished ADU that's ready to live in.

How It Works

Our ADU Construction Process

01

Consultation and Feasibility

We walk your property, evaluate the garage or yard, and give you an honest read on what your lot can support and what it will take to build.

02

Planning and Design Direction

We help shape the layout, finishes, and site plan around your goals, whether the unit is for rent, family, or work.

03

Permits and Approvals

We draw the plans, submit them, pull the permits, and answer the city’s corrections ourselves. You never wait in line at the building department.

04

Construction and Installation

Our crews handle foundation, framing, utilities, and finishes on an organized schedule with a clean, protected job site.

05

Final Walkthrough

We walk the finished ADU with you room by room, confirm every detail meets our standard and yours, and hand over a unit that is ready to live in.

§  What's Included

One team, one price, the whole ADU.

Everything below is part of the job and part of the fixed price we put in writing. No surprise trades to hire, no loose ends.

Sherman Oaks · Detached ADU
Sherman Oaks · Detached ADU
Design and plans: layout, elevations, and structural engineering for your lot
Permits and inspections: through LADBS or your city's building department, handled by us
Site work and foundation: graded, formed, and poured to plan
Framing and roofing: built like a real residence, because it is one
Plumbing, electrical, and HVAC: complete systems, run, connected, and inspected
Insulation and drywall: quiet, efficient, and finished clean
Kitchen and bathroom: cabinets, counters, tile, and fixtures installed
Flooring, paint, and finish work: move-in ready, inside and out
Final inspections and sign-off: we close out the permits so the unit is legal to occupy
2-year written warranty: on the workmanship, in your contract

Investment

What an ADU Costs in Los Angeles

In Los Angeles, a garage conversion ADU typically runs $100,000 to $180,000, while a detached new-build ADU commonly lands between $250,000 and $450,000. These are typical ranges, not quotes; size, utility connections, and site conditions all shape the final cost. Our ADU cost guide breaks the numbers down further.

Before you commit to anything, we do a free on-site walkthrough and build an itemized, line-item estimate. You approve a fixed price and timeline before construction starts, and that is what we hold to.

Financing is available for qualified homeowners. See remodel financing options in Los Angeles.

Transparent Pricing

ADU Cost in Los Angeles by Type

Real 2026 ranges for LA, not vague "starting at" teasers. Where you land depends on size, site conditions, and finishes.

ADU TypeTypical SizeTypical Cost (2026)Best For
Garage Conversion300–500 sq ft$100k – $180kFastest, most budget-friendly rental
Junior ADU (JADU)up to 500 sq ft$90k – $160kA suite within your existing walls
Attached ADU400–800 sq ft$180k – $320kExtra unit tied to the main house
Detached New-Build500–1,200 sq ft$250k – $450kA true second home in the backyard

Typical Los Angeles ranges for 2026, not quotes. Every project starts with a free on-site walkthrough and a fixed, itemized price in writing, that's the number we hold to.

Instant Estimate

Estimate Your ADU in Seconds

Pick a type and size for a real ballpark right now, no email wall, no waiting.

750 sq ft

Estimated project cost

0,000 – 0,000 Instant ballpark. Book a free on-site visit for a firm, fixed price.

Timeline

One Team, Fewer Months

Because the same team handles design, permits, and construction, there's no dead time waiting on one vendor to hand off to the next.

Athenian Builders
~3–5 months
Typical multi-vendor build
~9–14 months

Ranges vary with scope, size, and city review times. Detached new-builds run longer than garage conversions.

The Difference

Athenian vs. the Middleman

Most "ADU builders" are design shops or general contractors who sub the work out. We're one self-performing team, accountable start to finish.

 Athenian BuildersDesign-only / GC broker
Who builds itOur own crews, start to finish×Subbed out or you hire the GC
Your point of contactOne team, one number×Multiple vendors to juggle
The priceFixed & itemized, in writing before build×Often shifts after the design phase
Permits (LADBS)Handled by us×Sometimes left to you
TimelineFirm timeline in writing×Waits on subs' availability
Warranty2-year written workmanship warranty×Varies, often none

Why Us

Why Choose Athenian Builders Group

Clear Communication. You always know what is happening on your project, what comes next, and who to call.

Organized Project Management. We line up the trades, the deliveries, and the inspections so your build keeps moving instead of stalling.

Clean Workmanship. Tight joints, level lines, and finished details that hold up to a close look.

Real Construction Experience. We are builders first, with hands-on experience across every stage of ground-up construction.

Attention to Detail. The small decisions, from outlet placement to trim reveals, get the same care as the big ones.

Respect for the Property. We protect your home, your landscaping, and your neighbors’ goodwill with a clean, contained job site.

Los Angeles Area Experience. We build throughout LA County and know how local lots, hillsides, and the permit process shape a successful ADU.

★★★★★  5.0 Google Rating

Rated 5.0 on Google. Licensed and insured in California. CSLB License #1045030. Trusted Los Angeles ADU construction.

Our Portfolio

Related ADU Projects

Browse more ADUs we have built around Los Angeles: different lots, different layouts, different reasons for building.

Questions

ADU Construction FAQs

Most of our ADUs finish in 3 to 5 months. Garage conversions sit at the faster end, detached new builds take longer, and site conditions and permitting can move the schedule either way. You get a realistic timeline in writing during your free on-site estimate before work begins.

In most cases, yes. Many Los Angeles garages are strong candidates for conversion, and we assess the structure, foundation, and utilities during a feasibility visit to confirm exactly what yours will need.

Yes. We guide the design and planning of your ADU and pull permits through LADBS or your city’s building department, managing the paperwork and inspections so you are not chasing the city yourself.

Yes. We build ADUs as complete homes, and full kitchens, bathrooms, and laundry hookups are all part of what we can include so the unit functions independently.

ADUs need water, power, and sewer connections, and depending on the project these can be shared with the main house or set up with separate metering. We evaluate the options for your property and handle the utility work as part of the build.

We build ADUs throughout Los Angeles and all of LA County. Call (310) 857-2520 and we will confirm your location and schedule a free on-site visit.

Every project includes a written 2-year workmanship warranty. If our workmanship fails within two years of completion, we return and make it right at no cost. Your fixed price, timeline, and warranty are all stated in your contract before work begins.

Ready to Build Your ADU?

Call (310) 857-2520 or request a free on-site feasibility visit and estimate. We serve Los Angeles and all of LA County with clear, itemized pricing, so you know exactly what your ADU will cost before we ever break ground.

Prefer to text? Message us at the same number · We respond the same business day. Every project carries a written 2-year workmanship warranty.

Where We Build

Areas We Build ADUs

One self-performing team building design-led ADUs across Los Angeles County. Explore ADU construction, cost, and permitting for your city:

Proof

Recent ADU Builds in Los Angeles