LADBS plan check corrections decoded: what each correction actually means and how to address it

LADBS plan check corrections are written in code-speak. "Provide compliant LAMC §12.21 C.1 setback verification" tells you that something's wrong but not what to do about it. This guide decodes the 30+ corrections homeowners and architects encounter most often, by reviewer category, with the plain-language meaning and the cleanest fix.

Where corrections come from: about 70% of first-round corrections come from Zoning and Building (Structural). The remaining 30% spread across Energy, Plumbing, Electrical, Fire, and Mechanical. Most projects clear in 1-3 rounds; each round costs 1-3 weeks.

Quick answer

LADBS plan checks have up to 10 specialist reviewers (see the plan check pipeline guide). Each one can issue corrections. About 70% of first-round corrections come from Zoning and Building (Structural). The remaining 30% are spread across Energy, Plumbing, Electrical, Fire, and Mechanical. Most projects go through 1-3 rounds of corrections before approval. Each round adds 1-3 weeks to your timeline.

The fastest way to clear corrections is to understand what each reviewer is actually looking for before you submit. The categories below cover the ones that show up on most LA ADU projects.

Zoning corrections

The most common source of first-round corrections. Zoning reviews against LAMC §12.00-13.20 plus any applicable overlays.

"Setback verification not shown." The reviewer wants a clear, dimensioned distance from each property line to the proposed ADU. Fix: add explicit dimension callouts on the site plan from the ADU's nearest wall to the side, rear, and front property lines. Show the 4-foot state preempted minimum if you're tight on side or rear.

"FAR / lot coverage exceeded." Your proposed Floor Area Ratio or lot-coverage percentage exceeds the underlying zoning's cap. Fix: ADUs are exempt from FAR under state preemption (AB 68). Cite Gov Code §65852.2(c)(2)(A) in your correction response and clarify that the proposed structure is an ADU, not a non-ADU addition. If your lot coverage genuinely exceeds the cap (lot coverage is harder to argue exempt), reduce ADU footprint or shift design.

"Required ADU parking not provided." Zoning reviewer didn't catch the transit-proximity exemption. Fix: show that the property is within half a mile of a major transit stop on your title sheet, citing Gov Code §65852.2(d)(1)(A). Include the Metro stop name and walking distance. If you're not within transit proximity, you owe one off-street space (tandem or in setback area is fine).

"ADU size exceeds 1,200 sqft cap." The detached ADU is larger than the state-set maximum. Fix: reduce the footprint. The 1,200 sqft cap is state-set and cities cannot expand it (LA cannot approve over).

"Height exceeds 16 ft limit." Detached ADUs in LA are capped at 16 feet of height per state law (18 ft for ADUs within half a mile of major transit, with additional exceptions for two-story ADUs on lots with attached parking structures). Fix: lower the parapet or reduce roof pitch. The 16-ft measurement is from grade to the highest point of the roof. Confirm your elevation drawing matches that definition.

"Driveway dimensions non-compliant." The driveway approach width or angle doesn't meet LADBS standards. Fix: revise the site plan to show driveway width per LAMC §12.21 A.5 (typically 10 feet minimum), depth (typically 18 feet for residential), and the curb cut location. Coordinate with LA Bureau of Engineering if a new approach is needed.

Building (Structural) corrections

The second-most common source. Reviewers check structural calcs and load paths.

"Foundation calculations missing or incomplete." The submitted structural calc package doesn't show foundation sizing. Fix: have your structural engineer add foundation sizing calcs to the calc set. Standard items: footing size, reinforcing, soil bearing assumption (typically 1,500 psf default unless geotech says otherwise), foundation depth.

"Lateral system inadequate / shear wall schedule missing." The reviewer can't tell how lateral loads (seismic, wind) get from the roof down to the foundation. Fix: structural engineer adds a shear wall schedule showing wall type, sheathing thickness, nailing schedule, and hold-downs at corners. Include a lateral load path diagram in the plan set.

"Soil bearing assumption not supported." You assumed 1,500 psf but the reviewer wants confirmation. Fix: if you're on a hillside or in a liquefaction zone, you'll need a geotechnical report (soils report) confirming bearing capacity. Cost: $1,500-$4,000. On flat lots in non-liquefaction areas, the structural engineer can typically rely on standard 1,500 psf without a soils report, but document the assumption.

"Connection details inadequate." The framing-to-foundation, beam-to-post, or roof-to-wall connection details aren't specified. Fix: structural engineer adds detail callouts (Simpson tie sizes, bolt patterns, anchor specifications). Hold-downs at shear wall corners are the most-commonly missing detail on ADU submittals.

"Load path discrepancy at [location]." The reviewer can't trace how loads transfer through a specific area, usually around large openings, cantilevers, or unusual framing conditions. Fix: structural engineer adds a load-path narrative or supplemental detail for the area in question.

Energy / Title 24 corrections

California Title 24 Part 6. Almost every ADU triggers Energy corrections in some form.

"Title 24 documentation missing." The Cf-1R / Cf-2R (residential energy compliance) forms aren't in the plan set. Fix: have a Title 24 consultant or your designer generate the Cf-1R prescriptive or performance compliance form, signed and stamped. Include the form in the plan set. Cost: $300-$700 for a consultant to run the compliance software and produce the form.

"HERS verification not specified." The submitted Cf-1R requires HERS (Home Energy Rating System) verification on specific items (duct leakage testing, refrigerant charge, building envelope airtightness) but the plan set doesn't reference a HERS rater. Fix: add a note that a certified HERS rater will perform the required tests during construction. Identify the HERS items required by the compliance method you chose. Cost: $400-$900 for HERS verification.

"Window U-factor inconsistent." The U-factor and SHGC values on the window schedule don't match what's assumed in the Title 24 compliance form. Fix: align window specifications with the energy form, or update the energy form to match the specified windows.

"HVAC sizing calculation not provided." Manual J / Manual S / Manual D calculations aren't in the plan set. Fix: HVAC contractor or Title 24 consultant produces the load calc, equipment sizing, and duct sizing. Cost: bundled with Title 24 consulting typically. Required by code for any ADU with conditioned air.

Plumbing corrections

Reviewer checks against the California Plumbing Code (CPC, Title 24 Part 5).

"Vent sizing insufficient." The proposed vent pipe sizes are too small for the fixture units served. Fix: enlarge the vent pipe per Table 9.5.2 of the CPC. Common error: using 1.5-inch vent for fixtures requiring 2-inch.

"Fixture count wrong / DFU calc missing." Drainage Fixture Unit calculation hasn't been provided, or the calc total doesn't match the fixture count on the plans. Fix: add a DFU table to the plumbing plan showing each fixture, its DFU rating per CPC Table 7.2, and the cumulative load. Confirm the building drain and building sewer sizes match the cumulative DFU per CPC Table 7.3.

"Sewer connection details incomplete." The connection from the new ADU to the existing main sewer line, or to the public sewer lateral, isn't shown. Fix: add a detail showing the connection point, pipe slope (1/4-inch per foot for 3-inch and smaller), and any required cleanouts.

"Hot water heating undersized." The proposed water heater capacity is too small for the fixture load. Fix: either upsize the water heater (tankless is common for ADUs, typically 199K BTU for full bath plus kitchen) or document the load calculation supporting the proposed sizing.

Electrical corrections

Reviewer checks against the California Electrical Code (CEC, Title 24 Part 3).

"Service panel load calculation insufficient." The proposed electrical panel doesn't have capacity for the calculated load. Fix: redo the load calculation per CEC Article 220, including the new ADU's HVAC, water heater (if electric), appliances, and lighting. Either upsize the main panel, add a subpanel for the ADU, or use load-management equipment (smart panel) to argue capacity per CEC 220.87.

"GFCI / AFCI protection not specified." Required Ground Fault Circuit Interrupter or Arc Fault Circuit Interrupter protection isn't called out on the plans. Fix: add notes specifying GFCI protection at all required locations (kitchen counters within 6 feet of sink, bathroom outlets, garage, outdoor, basement, laundry) and AFCI protection on all branch circuits serving habitable rooms.

"EV-readiness not addressed." California code now requires new construction to be EV-ready (raceway, panel capacity for future EV charger). Fix: show a raceway from the panel to a designated EV parking location on the site plan, and reserve panel capacity for a 40-amp future circuit.

"Service grounding details missing." The grounding electrode system (ground rod, ufer ground in foundation, etc.) isn't detailed. Fix: add a grounding detail per CEC 250 showing the grounding electrodes and the grounding electrode conductor sizing.

Fire corrections

LA Fire Department reviews against the California Fire Code (CFC, Title 24 Part 9).

"Defensible space not shown (VHFHSZ)." You're in a Very High Fire Hazard Severity Zone and the plans don't show defensible space. Fix: add a defensible space plan showing the 100-foot perimeter cleared and managed per CFC Chapter 49. Show vegetation clearance zones, ember-resistant building features (vents, eaves, soffits), and fire-rated assembly callouts.

"Fire-rated assemblies missing." Walls or roof assemblies near property lines or in VHFHSZ zones don't show fire-resistance ratings. Fix: add fire-rated wall details (typically 1-hour rating using Type X gypsum board) where required by CBC Table 705.5 (proximity to property line) or CRC Section R337 (wildland-urban interface).

"Emergency egress dimensions inadequate." A bedroom window doesn't meet emergency egress requirements (minimum 5.7 sqft openable area, minimum 24 inches in either dimension, sill height not over 44 inches). Fix: enlarge the window or relocate. Egress requirements apply to every sleeping room.

"Sprinkler requirements not addressed." The ADU exceeds the sprinkler-trigger threshold (typically over 3,600 sqft for single-family, but ADU rules per LAMC may differ). Fix: add an automatic fire sprinkler system designed per NFPA 13D. Cost: $2-$5/sqft additional.

Mechanical corrections

Reviewer checks against the California Mechanical Code (CMC).

"Combustion air sizing missing." A gas appliance (furnace, water heater) doesn't have specified combustion air. Fix: add a combustion air calc and provide the required free area per CMC 701. Direct-vent equipment doesn't require combustion air from the room.

"Duct routing not shown." The plans don't show how supply and return ducts connect equipment to registers. Fix: add a duct layout showing equipment locations, supply runs, return path, and any plenum spaces.

"Ventilation rates insufficient." The proposed ventilation system doesn't meet ASHRAE 62.2 standards (whole-house mechanical ventilation required per Title 24). Fix: specify a continuous exhaust fan (typically 50-80 CFM continuous) or a balanced HRV/ERV system. The Title 24 compliance form has a ventilation rate input that drives this.

How to avoid corrections in the first place

Most corrections trace back to four root causes:

1. Skipping the site-specific prep phase. Without a current survey, an overlay analysis, and a full title sheet, you submit incomplete and get sent back. Spend 2-4 weeks here even though it feels like delay; it saves a correction round.
2. Using a designer not familiar with LADBS practice. An out-of-state architect or a designer who's only done private-sector commercial work will miss LA-specific quirks (hillside disclosures, VHFHSZ requirements, the FAR-exemption-but-not-lot-coverage-exemption distinction).
3. Submitting before the structural calcs are done. Structural takes longer than design. Don't submit the architectural plan set until the structural engineer has produced and stamped the calc package.
4. Not checking the overlays at feasibility. A project on a Methane Zone parcel that doesn't include methane barriers in the design will get sent back the moment Zoning sees the overlay flag. Run the PermitPathLA wizard's feasibility check before you draw. Every overlay it surfaces is a correction you avoid later.

The fastest path through plan check: clear all four root causes BEFORE submittal. A clean first submission can clear in 5 days for a PRADU; a sloppy one can grind for 3 months across multiple correction rounds. Same project, same code, dramatically different timelines.

If you've already received corrections, work through them in order of effort: the cheapest fixes (adding a note, citing a code section) first, then the architectural revisions, then the structural revisions. Most corrections take a few hours of designer time to address. Some (load path on a complex framing condition, geotech-driven foundation upsizing) take days.

Run your address through the PermitPathLA wizard before you submit. The wizard's feasibility step surfaces every overlay applicable to your lot, so your designer can address each one in the initial submittal instead of catching them on the first correction round.

Caveats

The correction patterns above reflect the most common items LA projects see across 2024-2026. Specific LADBS reviewers can and do issue corrections beyond these. Code interpretations evolve; the California Title 24 code suite, LAMC, and LADBS Information Bulletins are revised regularly. Your specific correction notice should be addressed against the cited code section in the notice itself, not generalized from this guide. When in doubt, your licensed designer or architect is the authoritative party to interpret and respond to corrections on your project.