Civic Data Works · Plans catalog · City of Williams

City of Williams — preapproved ADU plans

City of Williams ( County) posts 3 preapproved accessory dwelling unit plans on its own website, verified 2026-08-03.

Agency: City of Williams
County
Plans posted: 3
Verified: 2026-08-03

What’s posted

The city's ADU Plans and Information page lists three named/sized plans — 20x20 Studio (367 sq ft), 20x30 One-Bedroom (559 sq ft), and 20x40 Two-Bedroom (747 sq ft) — each with a working, city-hosted PDF download link, plus a comparison handout.

Source: https://www.cityofwilliams.org/services/planning/adu_plans_and_information.php

Adversarial re-check: fetched the page twice independently (direct + reader-proxy). Both times returned the same three plans with real sizes and working PDF links, and no contract/purchase-with-designer language was found. Stayed posted.

Any other agency can adopt these plans

Cal. Gov. Code § 65852.27, added by Stats. 2023, ch. 759, amended by Stats. 2024, ch. 7 (SB 477) (§ 65852.27(a)(5)) lets any California local agency admit into its own program plans “A local agency may also admit the following accessory dwelling unit plans into the program: (A) Plans that have been developed and preapproved by the local agency. (B) Plans that have been preapproved by other agencies within the state.” A city or county without a preapproval program of its own can post City of Williams’s plans as part of its own program instead of designing new ones — see the full statewide catalog for more options.

We build and maintain the program page, the plan library and the required third-party submission path for agencies that want to stand this up: $1,950 setup + $3,600/year (year one all-in $5,550).

Get started — $1,950 setup Questions? Email [email protected]

Data from Civic Data Works’ AB 1332 compliance scan. If City of Williams’s plans have moved or you find an error, write to [email protected] and we will correct this page. Back to the full catalog.