Design · 10 min read · March 3, 2026 · 481 words
Title 24 for ADUs: what actually triggers compliance
California's energy code is the single biggest design constraint after setbacks. Here's what Title 24 Part 6 requires for new ADUs in 2025 — heat pumps, fenestration, envelope, and the CF1R signoff.
Key takeaways
- Walls: R-21 cavity + R-5 continuous insulation in CZ8/9 (covers most of LA).
- Roof/ceiling: R-38 cavity for vented attics, R-30 + cool roof for unvented.
- Slab edge: R-7 to a depth of 16 inches.
Answered in this guide
Jump straight to the question you came in with — every answer is on this page, with links onward to the deeper guide.
- I'm in an HPOZ — can I still build?
- What setbacks and height limits apply?
- Are you licensed and insured?
- Do you use one crew or subcontractors?
- How does the contract work?
- What if I already have plans?
More across the studio · the full FAQ map · the reference desk
California's Title 24 Part 6 Energy Code is enforced on every new ADU. The 2022 code (in effect since Jan 1, 2023) made heat pumps the prescriptive default. The 2025 update, effective Jan 1, 2026, tightens envelope requirements and pushes solar-ready provisions further. This guide covers what triggers compliance and what an LADBS plan checker actually looks for — and how the answer reshapes your utility connection plan.
Prescriptive vs performance path
There are two routes to compliance. The prescriptive path is a checklist of minimum components (R-values, U-factors, equipment efficiencies). The performance path runs an energy model in CBECC-Res and shows the design beats a code-defined baseline. Most detached ADUs use the prescriptive path; attached ADUs and conversions usually need performance modeling — see detached vs attached vs conversion for the structural context.
Heat pumps are the new default
Under the 2022 code, gas furnaces and gas water heaters are still legal but trigger compliance penalties on the energy budget. The path of least resistance is a heat pump space heater (mini-split or central) and a heat pump water heater. The ENERGY STAR cold-climate heat pump list is a good starting point — though LA basically never needs cold-climate models.
Envelope requirements at a glance
- Walls: R-21 cavity + R-5 continuous insulation in CZ8/9 (covers most of LA).
- Roof/ceiling: R-38 cavity for vented attics, R-30 + cool roof for unvented.
- Slab edge: R-7 to a depth of 16 inches.
- Windows: U-factor ≤ 0.30, SHGC ≤ 0.23 (west and south orientations).
- Air leakage: blower-door tested at ≤ 5 ACH50.
Solar-ready and EV-ready
ADUs detached from the primary dwelling are required to comply with solar-ready provisions: a clear roof area facing within 110° of true south. ADUs are exempt from the actual PV requirement that applies to new single-family homes — but if the primary dwelling triggers it, an LADBS plan checker may ask. EV charging: a single 240V outlet in an accessible location is the minimum for any new ADU with a parking space.
The CF1R signoff
Every Title 24 submittal needs a Certificate of Compliance (CF1R) signed by a Certified Energy Analyst. This is the document LADBS stamps. Plan check rejects almost always trace back to a CF1R that doesn't match the architectural drawings — windows on the floor plan that aren't on the CF1R, or HVAC equipment that isn't listed on the CEC Appliance Database. The 2025 permitting rulebook covers what else has to land in the intake packet alongside it.
Sources
- Title 24 Building Energy Efficiency Standards · California Energy Commission
- CBECC-Res Compliance Software · California Energy Commission
- ENERGY STAR Heat Pump Criteria · U.S. EPA
- California Association of Building Energy Consultants · CABEC
- CEC Modernized Appliance Database · California Energy Commission
Next chapter · 01 of 03
Process · 8 min read
LADWP, SoCalGas and your ADU: the utility connection map
Going all-electric to comply also reshapes how you connect to LADWP — and whether you call SoCalGas at all.
Power, water, and gas hookups account for $8K–$35K of an ADU budget and 4–14 weeks of schedule. A walkthrough of the actual approval paths in 2026.
FAQ · Design
Common questions on design
The questions readers send us most after this guide.
I'm in an HPOZ — can I still build?
Yes, but with design review. Historic Preservation Overlay Zones require Certificate of Appropriateness from the cultural heritage commission before permits issue. We've shepherded projects through Miracle Mile, West Adams, Whitley Heights, and Spaulding Square HPOZs. Add 8–12 weeks for the COA process.What setbacks and height limits apply?
Statewide ADU law (AB 68/881) overrides most local restrictions: 4-foot side and rear setbacks, 16-foot height for detached one-story, 18-foot for two-story within ½ mile of transit. Front setbacks follow the underlying zone. We model your envelope at the schematic stage.Are you licensed and insured?
Yes — CSLB #1156772. License, bond, general liability and workers' comp certificates are shared during your consultation; full coverage details are confirmed in writing before signing.Do you use one crew or subcontractors?
We carry our own foreman, framers, and finish carpenters in-house. Specialized trades — MEP, roofing, glazing, solar — are long-standing subcontract relationships, the same crews on every project. You will know every face on your site by week three.How does the contract work?
Two phases. Phase 1 is a fixed-fee design + permitting agreement (typically $18K–$32K depending on scope) that takes you from feasibility through permit-in-hand. Phase 2 is a fixed-price construction contract issued only after permits are approved — no surprise change orders for items we should have caught at design.What if I already have plans?
We're happy to build off owner-supplied plans, with a brief constructability review first. Pricing is typically 5–8% lower than design-build because we skip Phase 1. We do require structural and Title 24 to be stamped by California-licensed professionals.
Reference desk · Design
More answers from the California reference desk
City-specific questions pulled from our 5,000-answer FAQ corpus — every link opens a deeper desk page.
What size ADU makes sense in Beverly Hills?
In Beverly Hills, the sweet spot for ROI is 600–850 sq ft (one-bedroom) — large enough to rent at $3,400/mo, small enough that $/sqft stays controlled and the permit path stays state-law-protected. Footprint and roof shape matter more than total square footage for the final number.What Title 24 requirements apply to a ADU in Beverly Hills?
CA Title 24 Part 6 (2022) requires high-efficiency envelope, mechanical, and lighting on any conditioned addition or new structure. The 2023 update mandates heat pumps for space and water heating on most new residential scopes — gas is allowed only with specific exceptions. Compliance is documented through a Title 24 report bound into the permit submittal; expect $1,800–$3,400 in compliance fees plus the equipment cost premium of $4K–$9K versus a gas system.What finish level should I specify for a ADU in Beverly Hills?
Spec for the rent target, not for personal preference. A $3,200/mo rental wants Bosch 500, quartz, LVP, and clean tile — not Sub-Zero and marble. In Beverly Hills, the workhorse tier (LG STUDIO appliances, KraftMaid cabinets, quartz, porcelain tile) delivers 85% of the daily-use experience of luxury tier at 55–60% of the cost.What layout works best for a ADU in Beverly Hills?
For a Beverly Hills ADU, the most successful layouts share three traits: (1) entry separated from the primary home for tenant privacy, (2) kitchen + bath stacked on a shared wet wall to reduce plumbing cost, (3) one larger main living area instead of two cramped rooms. Skip the breakfast bar — eat-in counters underperform a small dining nook in tenant satisfaction surveys.What exterior materials hold up best in Beverly Hills?
Beverly Hills climate rewards a small, proven palette: stucco or fiber-cement siding (James Hardie HZ10), Class A roofing (asphalt 30-yr architectural or standing-seam metal), aluminum-clad wood or fiberglass windows (Marvin, Sierra Pacific), and a low-maintenance landscape that doesn't trap moisture at the foundation. Avoid untreated wood siding in WUI fire zones — Class A assemblies are required.What size garage conversion makes sense in Beverly Hills?
In Beverly Hills, the sweet spot for ROI is 600–850 sq ft (one-bedroom) — large enough to rent at $3,400/mo, small enough that $/sqft stays controlled and the permit path stays state-law-protected. Footprint and roof shape matter more than total square footage for the final number.What Title 24 requirements apply to a garage conversion in Beverly Hills?
CA Title 24 Part 6 (2022) requires high-efficiency envelope, mechanical, and lighting on any conditioned addition or new structure. The 2023 update mandates heat pumps for space and water heating on most new residential scopes — gas is allowed only with specific exceptions. Compliance is documented through a Title 24 report bound into the permit submittal; expect $1,800–$3,400 in compliance fees plus the equipment cost premium of $4K–$9K versus a gas system.What finish level should I specify for a garage conversion in Beverly Hills?
Spec for the rent target, not for personal preference. A $3,200/mo rental wants Bosch 500, quartz, LVP, and clean tile — not Sub-Zero and marble. In Beverly Hills, the workhorse tier (LG STUDIO appliances, KraftMaid cabinets, quartz, porcelain tile) delivers 85% of the daily-use experience of luxury tier at 55–60% of the cost.What layout works best for a garage conversion in Beverly Hills?
For a Beverly Hills garage conversion, the most successful layouts share three traits: (1) entry separated from the primary home for tenant privacy, (2) kitchen + bath stacked on a shared wet wall to reduce plumbing cost, (3) one larger main living area instead of two cramped rooms. Skip the breakfast bar — eat-in counters underperform a small dining nook in tenant satisfaction surveys.What exterior materials hold up best in Beverly Hills?
Beverly Hills climate rewards a small, proven palette: stucco or fiber-cement siding (James Hardie HZ10), Class A roofing (asphalt 30-yr architectural or standing-seam metal), aluminum-clad wood or fiberglass windows (Marvin, Sierra Pacific), and a low-maintenance landscape that doesn't trap moisture at the foundation. Avoid untreated wood siding in WUI fire zones — Class A assemblies are required.What size JADU makes sense in Beverly Hills?
In Beverly Hills, the sweet spot for ROI is 600–850 sq ft (one-bedroom) — large enough to rent at $3,400/mo, small enough that $/sqft stays controlled and the permit path stays state-law-protected. Footprint and roof shape matter more than total square footage for the final number.What Title 24 requirements apply to a JADU in Beverly Hills?
CA Title 24 Part 6 (2022) requires high-efficiency envelope, mechanical, and lighting on any conditioned addition or new structure. The 2023 update mandates heat pumps for space and water heating on most new residential scopes — gas is allowed only with specific exceptions. Compliance is documented through a Title 24 report bound into the permit submittal; expect $1,800–$3,400 in compliance fees plus the equipment cost premium of $4K–$9K versus a gas system.
Sources & further reading
- California Government Code §65852.2 — statewide ADU framework (ministerial review, 60-day clock).
- LADBS — Accessory Dwelling Unit information bulletins and current permit fee schedule.
- HCD — California Department of Housing & Community Development, ADU handbook (2024 update).
- Internal data: aggregated from real California ADU and residential construction projects, 2018–2025.
Continue your read · the editorial path
We chained these chapters in the order LA homeowners actually need them. Each one picks up where the last one left a question open.
02 / 03
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The 2025 LA ADU permitting rulebook, decoded
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