Winnetka ADUs: what the permit data says

Winnetka has seen 630 ADU building permits issued since 2020, No. 14 in the City of Los Angeles. The count covers zip 91306.

Cantlay and Quartz Avenue, Los Angeles
Cantlay and Quartz Avenue. Photo: Busition, CC BY-SA 4.0, via Wikimedia Commons

Winnetka tracks the citywide mix closely: 30% of its ADU permits issued since 2020 are for units of 1,000 sf or larger, versus 27% citywide.

ADU permits issued by year

ADU building permits issued in Winnetka (91306), by year

64
2020
73
2021
104
2022
89
2023
105
2024
111
2025
84
2026
so far

How Winnetka builds

ADU types on permits issued in Winnetka since 2020

Garage conversion41.7% citywide 40.5%
Detached27.5% citywide 25.4%
Attached3.5% citywide 4.2%
Above garage0.0% citywide 0.5%

ADU types are classified from the free-text work description on each permit, and 27.3% of permits here could not be classified.

How big they build

715 sfmedian size on ADU permits issued since 2020 (citywide 684 sf)

Winnetka

Citywide

Under 500 sf32.8% citywide 33.1%
500 to 749 sf20.1% citywide 22.8%
750 to 999 sf17.5% citywide 16.9%
1,000 sf or larger29.5% citywide 27.2%

Permit records do not include bedroom counts, so we report sizes, not bedrooms.

$65,000

median declared valuation on permits (not market cost)

47.8%

have a Certificate of Occupancy so far (recent permits are still in progress)

2025

busiest full year, with 111 ADU permits issued

What this means

Counts are permits issued, not completed homes; some of these projects are still under construction and some will never break ground. The counts cover the City of LA portion of zip 91306, so anything outside city limits is not included. The busiest full year so far was 2025, with 111 ADU permits issued; the 2026 count runs through July only.

Count your backyard in.

Free test fit: could one fit behind your house? Test fits are quick estimates; humans verify before anything moves forward.

The Census Bulletin tracks these numbers on the A-du blog.

Source: LADBS permits, LA City Open Data. Issued Jan 2020 to Jul 2026. Pulled Jul 30, 2026.

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