ADUs + Additions · Los Angeles
Build more from the property you already own.
We design beautiful, buildable ADUs and additions, from feasibility and floor plans to permits and construction preparation.
- 1Feasibility
- 2Design
- 3Plans
- 4Permits
- 5Build preparation
What an ADU can do for your home.
Most Los Angeles lots have room for more than they hold today. An ADU turns that unused space into a home for family, a place to work, or a source of income.
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More living space
A bedroom, a suite or a whole second home without moving.
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Guest accommodations
Visitors get privacy, and so do you.
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Multigenerational living
Keep parents or grown kids close, with their own front door.
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Office or studio
A short walk across the yard instead of a commute.
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Rental potential
A legal second unit that may help offset what you pay to own.
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More use from your land
A well-designed ADU can add utility and long-term value to the property.
Rental income and property value depend on your property, the market and many other factors. We help you plan, but we don't promise specific financial results.
What could you build?
Five ways to add space. Open any of them to see typical sizes and what to plan for.
Drawings: existing structures in white, new work in tone. Sizes reflect general California ADU rules. Your city and lot decide the final numbers.
What a finished ADU feels like.
Light-filled small homes in plaster, oak and stone, designed to feel larger than their square footage.
Concept designs shown. Not completed client projects.
The options side by side
A quick way to see which direction fits your lot, budget and plans.
| Type | Detached | Attached | Garage conversion | Junior ADU | Addition |
|---|---|---|---|---|---|
| Typical size | Up to 1,200 sq ft | Up to 50% of home, 1,200 max | Garage footprint | Up to 500 sq ft | Set by zoning |
| Separate unit | Yes | Yes | Yes | Yes, inside the home | No, part of the house |
| Privacy | Highest | High | High | Moderate | Shared home |
| Relative cost | Highest | High | Lower | Lowest | Varies |
| Can be rented | Yes | Yes | Yes | Yes, rules apply | No |
| Best when | You have yard space | Back yard is tight | Garage is underused | You have a spare suite | You need a bigger house |
Additions and more square footage.
Sometimes the right move is a bigger, better main house instead of a separate unit. We design additions that look like they were always there.
Additions we design
- Room and primary suite additions
- Second-story additions
- Bump-outs and kitchen expansions
- Converting attics, garages and basements
Good to know
- Additions follow standard zoning rules, not the streamlined ADU rules
- Structural and energy upgrades are often triggered
- We can compare an addition with an ADU for your goals
ADUs designed by people who think about how they get built.
We design with construction in mind from the first sketch, so the ADU you approve is one you can actually build on budget.
See what you can buildBudget checked as we design
We price as the design develops, not after the drawings are done.
Details builders can price
Clear plans and finish selections mean fewer surprises in contractor bids.
Value engineering up front
We find savings in structure, systems and materials before anything goes to bid.
From an idea to something you can build.
The ADU path, from property check to a construction-ready project.
Start with step one-
01
Property check and feasibility
We review zoning, setbacks, utilities, easements and access to confirm what your lot allows.
You get a clear summary of what can be built and a starting budget range.
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02
Concept design
Site plan options and early layouts that balance space, light, privacy and cost.
You get two or three directions to react to.
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03
Design development
Floor plans, exterior elevations, 3D renderings, kitchen and bath design, and finish selections.
You understand the layout and design before it's drawn for permits.
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04
Permit plans and consultants
Permit drawings plus structural engineering, Title 24 energy, surveys and other reports, through licensed professionals.
You get a complete, coordinated permit set.
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05
Permitting
We submit, track plan check and handle corrections with the city until the permit is issued.
You get an approved permit, without chasing the city yourself.
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06
Pre-construction
Detailed budgeting, value engineering, bid packages and contractor coordination.
You start construction with a real number and a ready team.
ADU Property Check
Let's see what your property can do.
Answer a few quick questions. Not sure about something? Pick “Not sure” and we'll look it up.
- Takes about two minutes
- No technical knowledge needed
- We follow up within one business day
ADU questions, answered.
Don't see yours? Schedule a consultation and ask us directly.
Can I build an ADU on my property?
Most single-family lots in Los Angeles can have at least one ADU, and many can have an ADU and a Junior ADU. Lot shape, easements, hillside rules, fire zones and utilities affect what fits. The Property Check is the fastest way to find out for your address.
How much does an ADU cost in Los Angeles?
It depends on size, type, site conditions and finishes. Garage conversions and Junior ADUs usually cost the least, and new detached ADUs the most. We give you a starting budget range during feasibility and refine it as the design develops, so there are no surprises at bid time.
How long does it take?
Design and permitting often take several months, depending on the city, the complexity of the site and how quickly decisions are made. Construction usually follows over several more months. We give you a timeline for your specific project after the feasibility review.
Do you build the ADU too?
We take your project through design, permits and pre-construction, then coordinate with a licensed general contractor for construction. You get a budget, bid package and contractor ready to go.
Are you architects?
No. Casa Forma is a residential design and planning studio, not a licensed architecture firm. When an ADU legally requires a licensed architect, engineer or contractor, we coordinate with appropriately licensed professionals and tell you who holds each responsibility.
Do I need to know my lot size or zoning?
No. Give us your address and we'll pull the property details. Estimates are fine for everything in the Property Check.
Can I rent out my ADU?
In most cases, yes. ADUs can usually be rented long term. Short-term rental rules, Junior ADU owner-occupancy rules and rent regulations vary by city, so we review what applies to your property.
What does the Property Check cost?
Nothing. It's a free first look at your property and goals. If it makes sense to go further, we'll explain the feasibility and design options and what each one costs.
Ready to talk through your ADU?
A 30-minute call about your property, goals and budget. No obligation.