What Adus Actually Cost in Beverly Hills

Building an Accessory Dwelling Unit in Beverly Hills in 2026 will typically cost between $380,000 and $650,000 for a quality, detached new build. While a full new construction project commands a premium, a simpler project like a Junior ADU (JADU) within the main house or a basic garage conversion can start lower, in the $190,000 to $250,000 range, but these are less common in this market.

In a Nutshell: Beverly Hills ADU Costs

• Total Cost Range: $380,000 to $650,000+ for a new detached unit.
• Mid-Range Average: Approximately $475,000 for a 600-square-foot, well-appointed ADU.
• Typical Timeline: 12 to 18 months from initial design to final inspection. Permitting alone in Beverly Hills can take four to six months.
• Biggest Surprise Cost: Site preparation and utility trenching. On hillside lots or properties with dense landscaping, this can easily add $30,000 to $50,000 to the budget.

What does an ADU actually cost in Beverly Hills in 2026?

The total ADU cost in Beverly Hills is a story of three tiers, driven by the scope of work, quality of materials, and complexity of the site. Below is a breakdown for a typical 600-square-foot detached ADU, a common size for adding a one-bedroom unit.

Tier	Cost Range	Key Features
Basic ADU	$380,000 - $450,000	Standard grade finishes, simple rectangular footprint, level lot, minimal site prep, builder-grade appliances.
Mid-Range ADU	$450,000 - $575,000	Custom cabinetry, stone countertops, upgraded flooring, more complex roofline, moderate site work, energy-efficient appliances.
Premium ADU	$575,000 - $700,000+	Architect-designed, luxury finishes (e.g., Sub-Zero/Wolf appliances), custom millwork, extensive landscaping, challenging hillside site.

For a representative mid-range $475,000 project, here is where the money goes:

• Permits, Design & Engineering (15-20%): $71,250 - $95,000
• Foundation & Site Prep (10-15%): $47,500 - $71,250
• Framing & Structure (15-20%): $71,250 - $95,000
• Exterior Finishes (Roofing, Siding, Windows) (10-15%): $47,500 - $71,250
• Interior Finishes (Drywall, Flooring, Paint) (15-20%): $71,250 - $95,000
• Plumbing & Electrical Systems (10-15%): $47,500 - $71,250
• Kitchen & Bath (10%): $47,500
• Contingency (5-10%): $23,750 - $47,500

The bottom-of-range projects, like a garage conversion, achieve their lower cost by using the existing foundation and structure. This saves significantly on demolition, grading, and framing, but these projects still require extensive upgrades to meet Title 24 Part 6 (California Energy Code) and local seismic standards.

Why is it more expensive in Beverly Hills than the rest of Los Angeles?

Three primary factors lift the cost of a Beverly Hills ADU well above projects in surrounding areas like West Hollywood or the San Fernando Valley.

1. Stringent Permitting and Design Review: Beverly Hills operates its own Community Development Department, which is separate from the Los Angeles Department of Building and Safety (LADBS). The review process is known for being exceptionally detailed, with a strong emphasis on aesthetic continuity and neighborhood character. This often requires more extensive architectural plans, shadow studies, and material sample submissions, increasing upfront soft costs by $15,000 to $25,000 compared to an LADBS submission.

2. Higher Labor Costs and Contractor Premiums: The pool of contractors qualified and insured to work in Beverly Hills is smaller and in high demand. According to the California Department of Industrial Relations prevailing wage data for Los Angeles County, skilled labor rates are already high, but contractors working in Beverly Hills often add a premium of 15 to 20 percent. This covers logistical challenges like limited street parking for crews, restricted work hours, and the higher insurance liability required for working on multi-million dollar properties.

3. Land and Site Complexity: Many properties in Beverly Hills, especially north of Sunset Boulevard in areas like Trousdale Estates, are on hillsides with challenging soil conditions. This necessitates extensive geological and soil reports, engineered retaining walls, and often requires caisson foundations, which can add $50,000 to $100,000 to the project cost before framing even begins. Even on level lots in The Flats, property lines are tight, making access for heavy equipment difficult and expensive.

What do real Beverly Hills homeowners spend in 2026?

Three representative projects from 2026, scoped similarly, reconstructed from Golden Yards Magazine's Project of the Day network and used here in aggregate form:

• Project 1: The Pool House Conversion ($285,000): A 450-square-foot existing pool house was converted into a full ADU. The project reused the foundation and basic structure but required a new sewer line, a kitchen and bathroom build-out, and significant upgrades to insulation and windows to meet Title 24 energy standards. The final cost was higher than a typical conversion due to the need to match high-end existing finishes.
• Project 2: The Detached Guest House ($490,000): A new-construction, 650-square-foot detached ADU was built on a level lot behind the main residence. The cost reflects custom millwork, high-end bifold doors opening to the garden, and extensive trenching to connect to utilities located at the front of the property. The permit process with the Beverly Hills design review board took seven months.
• Project 3: The Hillside Studio ($620,000): An architect-designed 550-square-foot ADU built into a hillside. Over $120,000 of the budget was allocated to a new concrete retaining wall and engineered foundation. The project required specialized contractors for the structural work and faced significant logistical challenges getting materials to the site, driving up labor costs.

Where does the money actually go? Hidden ADU costs

Your contractor's initial bid often covers the core construction, but several significant costs for an ADU in Beverly Hills are frequently itemized separately or emerge during the process. Plan for these.

• Geotechnical and Soils Report: $3,000 - $8,000. Essentially mandatory for any new foundation in Beverly Hills, especially on sloped lots.
• Structural Engineering: $8,000 - $20,000. Complex designs or hillside construction require extensive engineering work to meet California's seismic codes.
• Beverly Hills Plan Check and Permit Fees: $15,000 - $30,000. Substantially higher than in many other cities due to the thoroughness of the review.
• Utility Connection Fees (LADWP/SoCalGas): $10,000 - $25,000. The cost to run new water, sewer, electrical, and gas lines from the street or main house can be extensive. The Los Angeles Department of Water and Power (LADWP) fees are a significant part of this.
• Title 24 Part 6 Energy Report and HERS Testing: $1,500 - $3,000. Required by state law, this verifies the ADU's energy efficiency through calculations and on-site testing.
• Landscaping and Hardscaping: $10,000 - $40,000. The cost to repair the yard after construction and add patios, walkways, or privacy fencing is rarely in the base construction bid.
• High-End Appliance Package: $15,000 - $35,000. Standard contractor bids include mid-grade appliances. The brands expected in a Beverly Hills property (e.g., Viking, Miele) are a significant upgrade.

What stops a Beverly Hills ADU from running over budget?

Cost overruns on high-stakes projects are common, but they usually stem from a few predictable sources. Awareness is the first step in prevention.

1. Unforeseen Site Conditions: This is the number one cause. On older Beverly Hills properties, you might discover undocumented fill soil, abandoned septic tanks, or rock formations during excavation. This can cause delays and require costly engineering solutions. The National Association of Home Builders recommends a ten to fifteen percent contingency on renovations in homes over thirty years old; for new construction on these lots, that advice is doubly important.

2. Scope Creep and Finish Upgrades: It starts with a small change, like upgrading the tile in the bathroom, and can cascade into thousands of dollars in change orders. Deciding on every single finish, fixture, and paint color before construction begins is the best defense. Lock in your choices and resist the urge to make changes once work is underway.

3. Permit and Inspection Delays: While California's AB 68 (the 2019 ADU shot-clock law) aims to speed up approvals, the Beverly Hills design review process adds a significant, and sometimes unpredictable, layer. A request for revisions can add weeks or months to the timeline, increasing carrying costs and potentially causing scheduling conflicts with your contractor.

You can get a rough estimate of your project costs before speaking to a contractor. Use our ADU Cost Calculator to model different sizes and finish levels for the Los Angeles area.

What should your Beverly Hills contractor include in the quote?

A detailed, itemized quote is non-negotiable. It protects you and the builder by creating a clear understanding of the project scope. Ensure your contract includes the following line items. For a complete guide on the local rules, see our Beverly Hills ADU Permit Playbook.

1. A detailed scope of work describing all phases of construction.
2. Architectural and structural engineering plan costs.
3. All city plan check, permit, and impact fees.
4. Site preparation, including demolition, grading, and excavation.
5. Geotechnical report and soil testing costs.
6. Foundation costs, specifying type (e.g., slab-on-grade, raised with cripple walls).
7. Lumber, framing, and sheathing materials and labor.
8. Exterior finishes: siding, stucco, roofing, and trim with material specs.
9. Windows and exterior doors with brand and model numbers.
10. Plumbing, electrical, and HVAC system costs, including trenching and hookups.
11. Insulation and drywall, including texture and finish level.
12. Interior finishes: flooring, paint, and trim with allowances per square foot.
13. Cabinetry, countertops, and appliances with specific brands or allowances.
14. A clear policy on change orders, including pricing and approval process.

The Golden Yards Magazine Take

The core challenge of building an ADU in Beverly Hills isn't just the high cost of labor and materials; it's navigating the city's deeply ingrained culture of architectural preservation and aesthetic control. Unlike projects under LADBS jurisdiction, where compliance with state laws like AB 68 and AB 1033 (the 2024 condo-style ADU rule) is more straightforward, Beverly Hills adds a subjective layer of design review. This process can feel opaque to homeowners and even experienced contractors. The most successful projects are not led by the fastest or cheapest builder, but by an architect-and-builder team with a proven track record of getting plans approved by the city's review board. Investing heavily in this specialized local expertise during the design phase is the single most important factor in controlling costs and timelines down the road.

Sources & Methodology

See the Golden Yards Methodology for how sources are reviewed, ranges are normalized, and planning-data limits are handled.

Cost ranges in this guide draw on the following named industry sources, public agency datasets, and Golden Yards Magazine editorial research.

• City of Beverly Hills Community Development Department, ADU Guidelines (2026)
• California Department of Industrial Relations, Prevailing Wage Determinations (Los Angeles County) (2026)
• National Association of Home Builders (NAHB), Construction Cost Survey (Q4 2025)
• California HCD, Accessory Dwelling Unit Handbook (2025)