Build an ADU
That Works
For Your Life
Maximize your property's absolute potential with a fully permitted Accessory Dwelling Unit. 4 Seasons manages design, engineering, local structural permissions, and turnkey general contracting from start to finish — completely unified under one license.
A Second Unit on Your Existing Lot
An Accessory Dwelling Unit (ADU) — also called a granny flat, backyard cottage, or in-law suite — is a fully independent living space built on the same property as your primary residence. It has its own entrance, kitchen, bathroom, and sleeping area.
Recent updates to California ADU law have made it easier and more affordable than ever to build. Setback requirements have been reduced to just 4 feet, parking minimums have been relaxed, and permitting timelines have been streamlined — making now an ideal time for Los Angeles homeowners to invest.
Whether you want to house a family member, generate rental income, or simply increase your property's value, a professionally built ADU is one of the highest-ROI investments you can make in Greater LA.
ADU Benefits at a Glance
- Rental IncomeGenerate $2,500–$4,500/month to offset mortgage costs or build long-term wealth.
- Property ValueA permitted ADU can add 20–30% to your home's appraised value in LA markets.
- Multi-Generational LivingKeep family close with independent space — no shared walls or schedules.
- Avoid the MoveExpand your home's capacity without the cost and disruption of relocating.
- Fully PermittedEvery ADU we build is city-permitted — protecting your investment and insurability.
Every Type of ADU, Built Right
We have experience building every category of Accessory Dwelling Unit in Los Angeles. Our team will recommend the best type based on your lot, goals, and budget.
Detached ADU
A completely separate structure in your backyard. Offers maximum privacy for tenants or family, and commands the highest rental rates. Ideal for lots with 5,000+ sq ft.
Most PopularAttached ADU
An addition connected to your main home sharing at least one wall. More cost-efficient to build than detached, with reduced foundation and utility connection costs.
Cost-EfficientGarage Conversion ADU
Transform your existing garage into a fully livable, permitted unit. Often the fastest and most affordable ADU option since the structure already exists.
Fastest BuildJunior ADU (JADU)
Up to 500 sq ft within your existing home's footprint. Ideal for converting a bedroom or basement. Lower cost, streamlined permitting, no separate utility meters required.
Lowest CostYour ADU, From Concept to Keys
We manage every phase of your ADU project under one roof. No separate architects, no coordination headaches — just one team fully accountable from day one.
Free Consultation & Site Assessment
We visit your property, review zoning rules, setbacks, and utility connections. You'll leave with a clear sense of what's possible and realistic cost ranges.
Week 1Custom Design & 3D Rendering
Our design team creates architectural plans and photo-realistic 3D renderings so you can see exactly what your ADU will look like before anything is built.
Weeks 2–4Engineering & Structural Plans
Licensed structural and civil engineers produce complete permit-ready drawings. We handle all coordination, so nothing falls through the cracks.
Weeks 4–8City Permit Submission
We submit directly to the City or County of Los Angeles and manage all back-and-forth with the permit office. You never have to deal with the bureaucracy.
6–12 WeeksConstruction
Our licensed crews build to spec with premium materials. Your dedicated project manager provides weekly updates and manages all inspections and subcontractors.
4–8 MonthsFinal Inspection & Handover
We complete the final city inspection, walkthrough punch-list, and hand you the keys — with a full warranty and continued support for any post-completion needs.
Week FinalOne Team. Total Accountability.
Most homeowners hire separate architects, designers, and contractors — then spend months managing the gaps between them. With 4 Seasons, there are no gaps.
Design-Build Under One License
Your designer and builder are the same team. What gets designed can be built within your budget — no expensive redesigns, no finger-pointing.
Faster Timelines
Design and permitting happen in parallel with procurement. Our integrated process cuts weeks off your project without cutting corners on quality.
One Point of Contact
Your dedicated project manager knows every detail of your build and is always reachable. No more chasing down separate trades.
Post-Completion Warranty
We stand behind every ADU we build. If anything needs attention after completion, you make one call — and we take care of it.
4 Seasons Remodeling & Design
Verified credentials & track record
What Does an ADU Cost in LA?
ADU costs vary based on type, size, site conditions, and finish level. Here are transparent ranges based on our completed projects in Greater Los Angeles.
Junior ADU / JADU
Conversion of existing interior space within the primary residence. Shares utility meters. Minimal structural work required in most cases.
Garage Conversion ADU
Converting an existing attached or detached garage. Structure already exists — cost goes toward habitability upgrades, insulation, HVAC, kitchen, and bath.
Detached / Attached ADU
New construction of a standalone or attached unit. Full foundation, framing, utilities, and finishes. Commands the highest rental rates and property value lift.
ADU Development
FAQs
Have a question not answered here?
Ask Us DirectlyReady to Build Your ADU?
Let's Talk.
Schedule your free in-home consultation with our team. We'll review your property, explain your options, and give you a clear, no-obligation estimate — no pressure, no vague ballparks.