LADBS data · City of Los Angeles · Trailing 12 months

LA ADU Inspection Index

Across the 8 ADU inspection types tracked in the City of Los Angeles, about 34% of inspections fail on the first attempt, based on 159,615 first-attempt inspections in LADBS records over the trailing 12 months. The rate varies by type: the highest, ADU Framing / Rough, fails on the first attempt in 47.2% of cases. Every figure below is computed directly from LADBS public records and refreshed weekly.

Source: LADBS 9w5z-rg2h Geo: City of Los Angeles Period: Trailing 12 months Last updated: July 1, 2026

Section 01

The ADU inspection sequence

A permitted ADU in Los Angeles is signed off through a series of inspections, each one checking a different stage of the build. An LADBS inspector visits the site, checks the work against code, and either approves it or issues a correction notice that must be fixed before the next stage proceeds. Roughly in order, a typical ADU passes through:

01Foundation & footing — the excavation, rebar, and slab before concrete is poured.

02Framing / rough — the structural skeleton once walls are up but before they are closed.

03Seismic shear wall — the bracing and hold-downs that keep the structure standing in an earthquake.

04Stucco & lath — the exterior lath and cladding before the finish coat.

05Electrical service / power release — the panel and service that lets the unit be energized.

06Gas shut-off valve (SGSOV) — the seismic gas shut-off protection.

07Smoke & CO detectors — life-safety devices required before occupancy.

08Final — the last sign-off that clears the unit for use.

The index below reports, for each of these types, how often the first attempt passes — how ready the work really was when the inspector arrived.

Section 02

First-time fail rate by inspection type

Inspection type First-time fail rate Sample (first attempts) Detail

ADU Final Inspection

Tier 1

34.7%

79,761

View page →

ADU Smoke & CO Detector

Tier 1

22.6%

15,786

View page →

ADU Electrical Service / Power Release

Tier 1

31.3%

15,566

View page →

ADU Gas Shut-Off Valve (SGSOV)

Tier 1

31.8%

9,406

View page →

ADU Stucco & Lath

Tier 2

23.6%

4,837

Tier 2 — coming soon

ADU Foundation & Footing

Tier 2

38.2%

5,615

Tier 2 — coming soon

ADU Seismic Shear Wall

Tier 2

23.4%

7,707

Tier 2 — coming soon

ADU Framing / Rough

Tier 2

47.2%

20,937

Tier 2 — coming soon

Fail rate = share of permits whose first attempt at that inspection type did not pass, over the trailing 12 months. A first attempt counts as a failure when it received a correction notice or the work was not ready when the inspector arrived. Sample is the number of distinct first attempts the rate is based on. Types below the 100-inspection threshold are not shown. Source: LADBS 9w5z-rg2h, City of Los Angeles.

Section 03

Inspection types in detail

ADU Final Inspection

34.7% first-time fail · 79,761 inspections

ADU Smoke & CO Detector

22.6% first-time fail · 15,786 inspections

ADU Electrical Service / Power Release

31.3% first-time fail · 15,566 inspections

ADU Gas Shut-Off Valve (SGSOV)

31.8% first-time fail · 9,406 inspections

Section 04

Frequently asked questions

What does "first-time pass rate" mean?

It is the share of ADU inspections that pass on the very first attempt for a given permit and inspection type. We take each permit's first attempt at each inspection type and classify it as a pass or a fail. Work that failed for a correction, or that was not ready when the inspector arrived, counts as a fail; scheduled, cancelled, partial, and administrative records are set aside. We only count first attempts, so the number tells you how often work passes the first time rather than how often it eventually passes.

Where does the data come from?

From the Los Angeles Department of Building and Safety (LADBS) public inspection dataset (Socrata 9w5z-rg2h). We recompute the figures weekly over a rolling 12-month window and publish the last-updated date on this page.

Is this all of California, or just Los Angeles?

Only the City of Los Angeles. The figures come from LADBS records for permits inside city limits, so they don't cover the rest of LA County or the state.

Why is the sample size shown next to every number?

So you can judge how solid each figure is. We only publish a rate when the first-attempt sample for that type clears our threshold of 100 inspections in the window; types below the threshold are marked "not enough data" and no percentage is shown.

Does a first-time failure mean the contractor is bad?

Not on its own. A single correction notice is routine in construction. What matters is the pattern — a contractor whose projects fail first inspection far more often than the city norm, across many permits, is a different signal than one occasional correction. This page reports the market-wide rate by inspection type, not any individual contractor.

How often do the numbers change?

The pipeline recomputes weekly. Each run publishes a new snapshot; this page always shows the most recent one, and the "Last updated" date reflects it. If a run fails, the previous snapshot stays live — you never see a half-computed number.

Methodology & authorship

Who publishes this index

ADUscale Research

The LA ADU Inspection Index is maintained by ADUscale, a California build-side ADU partner, using the inspection database behind our sister brand InspectPilot. Figures are computed directly from LADBS public records (9w5z-rg2h) over a rolling trailing 12 months and refreshed weekly. We report the market-wide rate by inspection type only — no contractor names, licenses, or personal data.

Last updated: July 1, 2026 · Geography: City of Los Angeles · Period: 2025-07-01 to 2026-07-01

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