Custom ADUs, designed around your lot and your life.
When a pre-designed plan won’t fit the lot or the way you’ll live — a hillside, a narrow side yard, an ADU above the garage, a home for two generations — we design it around what you tell us you need. A fixed design fee, quoted after a 15-minute Backyard Review, and plan check with your city managed end to end.
- $9,990–$19,990
- Fixed design fee, quoted after your Backyard Review
- 2–3 months
- From your first design meeting to permit-ready construction drawings
- 126
- ADU projects designed and permitted across Los Angeles since 2017
15-minute video call · No obligationOr try the Backyard Planner →
- Zero permits denied
- 126 LA ADU projects
- 5.0 on Google
Three ways to start a custom ADU.
Every path carries a fixed design fee, quoted in writing after your Backyard Review.
A Signature Home, modified Plan fee $7,490–$12,990 + $250/hr for changesEst. cost to build $180K–$420K 
A blank page Design fee $9,990–$19,990, fixed once quotedCost-to-build range from recent projects like yours 
The hard lot Feasibility on the call, before any feePriced per project after we walk the site Custom ADUs we've designed in Los Angeles.
Woodland Hills ADU
2 Bed, 2 Bath · 800 sqft · Woodland Hills, Los Angeles, CA
Design $9,990 · Built for $310,000 by an independent licensed GC
West Adams 2-Story ADU
3 Bed, 2 Bath · 1,200 sqft · West Adams, Los Angeles, CA
Design $12,990 · Built for $400,000 by an independent licensed GC
Reseda Craftsman ADU
3 Bed, 2 Bath · 1,200 sqft · Reseda, Los Angeles, CA
Design $11,990 · Built for $365,000 by an independent licensed GC
How a custom ADU goes from a 15-minute call to keys.
A custom ADU is a longer road than a pre-designed plan — 11 to 16 months from first call to move-in. Here is exactly where that time goes, and what you know at each step before you commit to the next one.
The Backyard Review
We screen-share to your address, look at the lot, the setbacks, and what fits, and listen to what you want to build. If a Signature Home — modified or as designed — would serve you better, we will say so. If custom is the right path, you leave the call knowing the design-fee range, a cost-to-build range from recent projects like yours, and the next step.
The site visit
We walk your lot with you: zoning, setbacks, height limits, utility capacity, what can actually be built, and a tighter cost-to-build range for it. It costs nothing and there is no deposit to schedule it. It is also what your fixed design fee is quoted from — once we have stood on the site, the number is the number.
Design & construction documents
Our design team draws your ADU one of one — floor plan, elevations, structural engineering, Title 24 energy compliance, and full construction drawings. You review and refine until it is exactly right. The fee is fixed when it is quoted; the only thing that changes it is a change you ask for.
Plan check & permit
We submit to your city and manage the entire plan check — corrections, resubmittals, follow-ups — at no added fee. Custom plans take longer than a permit-ready Signature Home, but nearly a decade of Los Angeles County permitting sits behind every submission.
Construction
Build with our construction partner or your own licensed contractor. The builder bids the finished drawings, so the number firms up as the design does — from a range on the first call, to a tighter range once we have walked the site, to a bid.
Looking for a custom ADU builder in Los Angeles? Here is how the work is split.
A custom ADU has two halves: the drawings and the permit, then the construction. We do the first half end to end and stay on the project through the second.
CALI ADU designs, engineers, and permits it
Architectural design, structural engineering, Title 24, and full plan-check processing with your city — 126 ADU projects across Los Angeles since 2017.
An independent licensed California general contractor builds it
Construction is performed by independent licensed California general contractors under a separate contract with you. Bring your own, or build with a contractor we have delivered custom projects with before. Either way the builder bids the finished drawings, so the number you sign is for your actual design. CALI ADU is not a licensed general contractor.
We manage the design through construction
Contractor questions, substitutions, and the inspections that touch the drawings all come back to us, so the home that gets built is the one that got permitted.
What a custom ADU costs: three numbers, in writing, before you commit.
Signature Home vs. custom ADU: the honest comparison.
We offer both paths and we will tell you which one we think is the better fit for your project.
Signature Home
- Plan fee $7,490–$12,990, fixed. Est. cost to build $180K–$420K, in writing.
- 6–9 months start to finish.
- Pre-designed and permit-ready — skip 2–3 months of custom drawings.
- Architect-designed floor plans, 400–1,200 sqft.
- 15,552 finish combinations per model through our à la carte configurator.
Custom ADU
- Design fee $9,990–$19,990, fixed once quoted. Cost-to-build range from recent similar projects, tightened after the site visit.
- 11–16 months start to finish.
- Fully bespoke design from a blank page.
- Unlimited floor plan, layout, and material choices.
- Ideal for unusual lots, non-standard footprints, or one-of-a-kind visions.
- Same team, same project oversight through plan check.
Not sure which path is right for you? That is exactly what the 15-minute Backyard Review is for. We look at your lot, listen to your vision, and recommend the path that gives you the best outcome for your budget and timeline.
When a custom ADU makes sense.
Your lot demands it
Steep hillside, irregular shape, extreme setback constraints, or limited access that a standard footprint cannot accommodate.
Your vision requires it
A specific architectural style, an unconventional layout, or a program — like a home recording studio or artist's workshop — that no pre-designed plan covers.
You have the timeline
Custom takes 11 to 16 months. If you need a home in under a year, a Signature Home at 6 to 9 months is the faster and more certain path.
See it on your lot. Then decide.
Whether you end up modifying a Signature Home or commissioning a fully custom ADU, every project starts the same way — a 15-minute Backyard Review where we screen-share to your address, look at what fits, and recommend the best path forward. No obligation.
Not ready to talk? Try the Backyard Planner →
Designed in-house · Fixed design fee · Plan check managed end to end