A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateHow Much Does Junior ADU & Interior Conversion Cost in Woodland Hills?
A Junior ADU (JADU) in Woodland Hills typically costs between $85,000 and $145,000 when converted from existing interior space like an attached garage or a spare bedroom wing. Smaller interior conversions with minimal plumbing work can run as low as $60,000, while full garage-to-JADU conversions with new foundation work, panel upgrades, and custom finishes can reach $180,000. Most homeowners we work with in Woodland Hills budget between $95,000 and $130,000 for a permitted, move-in-ready JADU with a kitchenette and private entrance.
These numbers reflect the current Woodland Hills market in 2026, including city permit fees, plan check, and typical contractor labor costs for the area. The price you pay depends on whether your existing space already has plumbing stubbed in, whether the electrical panel needs an upgrade, and whether you are working within the existing footprint or adding square footage.
Junior ADU & Interior Conversion Cost Breakdown (2026)
Here is what a Junior ADU conversion actually costs in Woodland Hills, broken down by scope. These are real working numbers from jobs we have priced in the area, including the Warner Center, Walnut Acres, and Vista de Oro neighborhoods.
| Scope of Work | Typical Cost Range (Woodland Hills) |
|---|---|
| Attached garage conversion to JADU (existing walls, slab floor) | $85,000 – $125,000 |
| Interior bedroom/bonus room conversion to JADU | $60,000 – $95,000 |
| Full JADU with kitchenette, bathroom, separate entrance | $110,000 – $145,000 |
| Prefab JADU (Abodu, Cover, or similar) including site prep | $120,000 – $180,000 |
| Electrical panel upgrade (if required) | $3,500 – $6,000 |
| Plumbing rough-in (new kitchenette or bath line) | $8,000 – $18,000 |
| City of LA plan check and permit fees (JADU) | $4,000 – $9,000 |
| HVAC mini-split system | $4,500 – $8,500 |
| Interior finishes (flooring, drywall, paint, trim) | $18,000 – $35,000 |
These ranges assume the existing structure is sound and you are converting space already inside the home’s footprint. If you are in an older Woodland Hills home south of Ventura Boulevard, plan for the possibility of structural reinforcement, termite repair, or outdated wiring, any of which can add $5,000 to $20,000 to the job.
At our Junior ADU & Interior Conversion page for Woodland Hills, we walk through the exact step sequence from first visit to final inspection. The numbers above are the pricing foundation we work from, and the price we hand you before work starts is the price on the final invoice. That is the Garrison Standard, and it has been since 2006.
What Affects Junior ADU & Interior Conversion Pricing in Woodland Hills
ZIP codes matter. Woodland Hills spans 91364, 91367, and part of 91303, and home styles shift a lot across that footprint. A 1960s ranch off Shoup Avenue with an attached two-car garage prices differently than a newer tract home north of the 101 with a finished bonus room. Here are the factors that move the number:
- Existing plumbing location. If your garage sits on a slab with no water lines and the bathroom drain is 40 feet away on the other side of the house, trenching and re-piping adds $8,000 to $18,000. If the space is adjacent to an existing bath or laundry line, the job gets cheaper fast.
- Electrical panel capacity. Many Woodland Hills homes built before 1990 have a 100-amp panel. A JADU with a kitchenette (small refrigerator, microwave, induction cooktop) and a mini-split typically requires 200-amp service. That panel upgrade, including LADWP coordination, runs $3,500 to $6,000 and adds about two weeks to the permit phase.
- Separate entrance requirements. The California Building Code requires a JADU to have its own exterior access. If your interior conversion space is at the back of the house with no exterior wall nearby, you are cutting a new door, framing a landing, and possibly adding a small stoop. Budget $6,000 to $12,000 for that alone.
- Setback and zoning factors in Woodland Hills. Some JADUs bump up against side-yard setback rules, especially on the narrower lots near Topanga Canyon Boulevard. If the city requires a setback variance (written permission to build closer to the property line than the standard rule allows), plan for additional plan-check time and a few thousand dollars in fees.
- Foundation condition. Garages in the older flats of Woodland Hills often have slab floors poured with no rebar and no vapor barrier. If the slab has shifted or cracked, you may need a section repoured before interior framing begins. We have seen this add $7,000 to $15,000 on homes near the Santa Monica Mountains where soil movement is constant.
- Finish level and appliances. A JADU can be a simple studio with a kitchenette and a shower, or it can look like a high-end ADU with quartz counters, custom cabinetry, and a stacked washer-dryer. The difference between builder-grade and custom finishes is $25,000 to $40,000 on the same floor plan.
How to Save on Junior ADU & Interior Conversion
The smartest way to save is to convert space that already has some infrastructure. A spare bedroom with a nearby bathroom and a window that can become a door will price far below a detached garage with no plumbing or power. Before you call any contractor, look at your floor plan and identify which interior space sits closest to existing water lines and the electrical panel. That one observation can drop the job by $20,000 or more.
Prefab is not automatically cheaper, but it can be faster. We work with Abodu, Cover, Dvele, Mighty Buildings, Boxabl, and Plant Prefab, and we tell homeowners the truth about each one: a prefab JADU may cost slightly more per square foot than stick-built, but the factory build shortens the on-site schedule by four to eight weeks. If you are carrying a mortgage on the main house while construction drags on, speed has real value. We also build conventionally with James Hardie siding when the budget favors a traditional route.
Do not skip the permits. Some Woodland Hills homeowners try to save the $4,000 to $9,000 in city fees by doing unpermitted work. The short-term savings evaporate when you try to sell, refinance, or get an insurance policy that knows the truth. A JADU built by the book appraises, insures, and sells clean. We do every job permitted, every time.
Finally, get a written price before any work starts. Not an estimate with a handshake. A written price. That is how we run every project at Fielding ADU Builders, because the number you approve on day one should be the number on the final invoice. If you want to talk through your space and get a real number for your specific lot, call us at (559) 254-0116. Estimates are free, and a live person answers the phone whether you call at noon or midnight.
FAQs – Junior ADU & Interior Conversion Cost
How much does a Junior ADU cost in Woodland Hills in 2026?
A Junior ADU in Woodland Hills costs between $85,000 and $145,000 for a permitted conversion of existing interior space, with most projects landing between $95,000 and $130,000. That includes design, permits, labor, and materials for a unit with a kitchenette, bathroom, and separate entrance. Give us a call at (559) 254-0116 and we will give you a written price for your specific space, free.
Is a Junior ADU cheaper than a full ADU?
Yes. A JADU converted from existing interior space typically runs 40% to 60% less than a detached ADU, because the foundation, roof, and exterior walls already exist. A detached ADU in Woodland Hills often starts around $180,000, while an interior JADU conversion starts around $60,000. The tradeoff is size: JADUs are capped at 500 square feet under state law.
Can I convert my attached garage to a Junior ADU?
Yes, and garage conversions are the most common JADU type we build in Woodland Hills. If the garage is attached to the main house and you are willing to sacrifice covered parking, the conversion usually runs $85,000 to $125,000 depending on plumbing and electrical work. The city requires you to replace the lost parking unless you qualify for an exemption, so add $3,000 to $8,000 for a new driveway or carport pad if needed.
How long does a Junior ADU conversion take in Woodland Hills?
A typical interior JADU conversion takes 8 to 14 weeks from permit submission to final inspection, with plan check at the City of Los Angeles running 3 to 6 weeks and construction running 5 to 8 weeks. Prefab units we source from Abodu or Cover can cut construction time to 3 to 5 weeks on site, but plan check still runs the same. We give you a written schedule with the written price, and we hit the window or we tell you why in real time.
Do you offer financing for Junior ADU conversions?
We do not offer in-house financing, but we work with homeowners who use HELOCs, cash-out refinances, and construction loans, and we price jobs so the lender sees a clean, permitted scope of work with no change-order surprises. The written price we hand you works as a loan document. Call (559) 254-0116 if you want to talk through what a lender will need.
Is a Junior ADU rental income worth the cost in Woodland Hills?
At a build cost of $110,000 and a Woodland Hills market rent of $1,800 to $2,400 per month for a JADU, the gross yield runs 19% to 26% annually, which pays back the build in 4 to 6 years. Your actual return depends on your financing cost, property taxes, and how long you hold. We are builders, not financial advisors, but we can show you the cost side clearly so you can run your own numbers.
Why Fielding ADU Builders Prices Differently
Reed Calloway leads Fielding ADU Builders, and the way we price is not complicated. We walk your space, we measure, we ask what you want, and we hand you a written price before a single nail is driven. That number covers the scope on the page, and the Garrison Code is the operating rule we have held since 2006: show up in the window, price in writing, by the book, leave it clean, stand behind it for a year. The 365-Day Done Right Promise is the written guarantee behind every project. If the work fails inside that year, we come back and make it right at no charge.
Every crew member who steps onto your Woodland Hills property is background-checked and arrives in uniform. You know exactly who is on your site, and a live person answers our phone 24 hours a day, 7 days a week. No voicemail, no callback queue. That matters when you are six weeks into a build and have a question at 7:30 on a Sunday morning.
Get a Written Price for Your Woodland Hills JADU
If you are ready to put real numbers against your floor plan, call us at (559) 254-0116. We will talk through the space you are considering, give you a working range over the phone, and schedule a free walk-through at your home. After that visit, you get a written price that does not move unless you change the scope. That is the whole point of the Garrison Standard.
We also invite you to start at our home page to see the full range of ADU and room-addition work we do across Woodland Hills and the wider San Fernando Valley.
Written by Reed Calloway, Owner at Fielding ADU Woodland Hills, serving Woodland Hills since 2006.
Pricing reflects the Woodland Hills market as of 2026. Fielding ADU Woodland Hills offers free estimates – call (559) 254-0116.
What Our Customers Say
"Solid job. Cabinet delivery was a week behind but they worked around it."
- Ben G."Room addition over the back patio. Framing is square, windows are tight, and the roofline matches."
- Danny L."Built a detached ADU behind our house. The builder is a veteran and runs the site like a platoon: schedule posted, crew on time, everything labeled. Finished within a few days of the date."
- Ken W.
