San Anselmo — Historic Preservation

Last reviewed: July 2, 2026

Overview

San Anselmo's zoning and planning ordinance embeds historic-preservation controls across several chapters (notably the zoning Chapter 3 / Title 10 articles on development standards, design review, and demolition, and the ADU chapter). The code protects buildings and districts by (1) requiring Planning Commission review for substantial demolition, (§ 10-3.2102) ; (2) treating properties in local historic districts or listed as Town landmarks as special cases for density/floor-area allowances and certain demolition/subdivision actions (§ 10-3.402 note/Table 4A; § 10-4.309) ; and (3) folding historic-sensitive standards into the accessory-dwelling-unit rules (ADUs) and design-review triggers (§ 10-6.302(g); § 10-6.303(e)(2); § 10-3.1501–1505) . For local context consult the San Anselmo zoning overview and the Town's Zoning pages.

IMPORTANT: this page summarizes what the San Anselmo ordinance text requires or restricts with respect to historic resources; always verify parcel-specific status with the Town (see "Verify with the jurisdiction" notes below).

How the code treats historic resources (quick map of authorities)

• Demolition controls and findings: § 10-3.2101–10-3.2105 (Demolition permit article) — Planning Commission review required for most building demolition above thresholds; submittal and consultant-report requirements apply.
• Design review protections: § 10-3.1501–10-3.1506 — design-review triggers and findings (special rules for R-1-H, R-1-C, and pre-1960 facades). See the Town's Design Review page for process context.
• ADU historic protections and exemptions: § 10-6.301–10-6.304 — objective ADU standards include a stand‑alone historic clause disallowing ADU-related exterior work that would adversely affect historic significance; ADU parking exemptions when an ADU is "located within an historic district." See the Town's ADUs summary.
• Development standards and exceptions for historic properties: Table 4A and related notes (Development Standards Table) exclude historic-district or Town‑landmark sites from certain density/FAR relaxations — Table 4A note and § 10-3.402. See the Town's Development Standards page.

District-by-district breakdown (historic-preservation relevance)

Note: San Anselmo's numeric Table 4A establishes district dimensional standards; this section lists the districts for which the ordinance explicitly ties special historic-preservation or design-review rules. For full permitted‑use tables and numeric setbacks/FARs consult Table 4A and the development standards sections.

R-1-H (Residential, Historic / Hillside)

• Purpose: preserve low‑scale, hillside residential character and minimize ridge/hillside visual impacts. R-1-H has more stringent design-review and ridge‑zone controls.
• Typical permitted uses: single‑family dwellings and accessory buildings consistent with residential use table (see Table 3A).
• Key dimensional / historic-related standards:
  • Ridge/hillside rule: no development on visible ridges/hillsides unless infeasible to avoid; if allowed, maximum height is 18 ft above the ridgeline (§ 10-3.404(b)). § 10-3.404(b)
  • Design review: all exterior modifications on R-1-H are subject to design review (§ 10-3.1505(b)); higher scrutiny for materials/visual profile. § 10-3.1505(b)
• Where it applies: properties mapped as R-1-H (see zoning maps); R-1-H also carries additional tentative-map and precise-development-plan requirements.

R-1-C (Residential, Conservation) and R-1

• Purpose: protect neighborhood character; R-1-C adds conservation/compatibility emphasis.
• Typical permitted uses: single‑family homes, accessory uses per Table 3A.
• Key dimensional / historic-related standards:
  • Ridge/hillside limits and visual‑profile requirements apply to R-1-C and R-1 (same 18 ft above ridgeline rule when development in ridge zone) (§ 10-3.404(b)). § 10-3.404(b)
  • Design review: many additions and exterior changes in R-1 and R-1-C are subject to design review; the code explicitly ties design‑review findings to scale and neighborhood compatibility (§ 10-3.1504–10-3.1506). § 10-3.1504–10-3.1506
• Where it applies: standard single‑family neighborhoods and conservation zones mapped in Town.

R-2 and R-3 (Lower- and higher-density residential)

• Purpose/Uses: R-2 allows duplexes/limited multifamily; R-3 covers larger multifamily, churches, and convalescent homes. Design‑review thresholds differ (multifamily/commercial triggers are broader).
• Key historic protections:
  • Design-review triggers for multifamily / commercial expressly protect facades built prior to 1960 from detrimental changes (§ 10-3.1504(f)). § 10-3.1504(f)
• Where it applies: as mapped in Town zoning (Table 3A / Table 4A).

Commercial / Mixed-Use (examples: C-N, downtown)

• Purpose: permit commercial uses with downtown character controls.
• Historic protections: exterior improvements and conversions in commercial zones are generally subject to design review; the code includes a protective finding that projects not be detrimental to facades constructed prior to January 1, 1960 (§ 10-3.1504(f)). § 10-3.1504(f)
• Where it applies: commercial corridors and downtown parcels where historic facades may exist. See the Town Land Use pages for mapping.

Most decision‑relevant standards & uses (quick table)

Practical guidance / interpretation (plain-English synthesis)

• If your property is a Town‑designated landmark or inside a designated historic district, expect additional procedural steps and stricter outcomes: no automatic density/FAR bonuses, limits on demolition, and stricter ADU review to prevent "adverse impacts" to historic significance (verify designation early). § 10-3.2102; § 10-3.402; § 10-6.302(g)
• For demolition: quantify the area in square feet (the code measures exterior wall demolition and includes windows/doors in the calculation) and be prepared to provide drawings, wall‑area calculations, possible structural verification, and an independent historic‑preservation architect report at the Town's request. § 10-3.2103
• For alterations on older commercial or multifamily buildings (notably facades pre‑1960) expect Commission review and findings addressing neighborhood character and visual impacts. § 10-3.1504(f)
• For ADUs: the Town permits ADUs but retains authority to deny changes that would harm a listed historic resource; ADUs in historic districts may also get parking exemptions but demolition of a detached garage tied to an ADU in a historic district requires more careful notice/review. § 10-6.301–10-6.304

Include the Town's design-review checklist and get early pre‑application advice when the property is historic — the Planning Department may require a consultant report that the applicant must pay for. § 10-3.2103(d)

Checklist

• Confirm whether the parcel is a Town landmark or inside a historic district (verify with Planning). (Verify with the jurisdiction)
• For demolition: if proposed exterior demolition exceeds 50% of exterior walls, prepare a demolition permit application including wall-area calculations, drawings, and (if requested) a preservation‑architect report. § 10-3.2102–2103
• If proposing exterior changes: determine whether design review applies (many R‑1‑H, R‑1‑C, commercial and multifamily changes do). § 10-3.1504–1505
• For ADUs: prepare ADU objective‑standards materials (site plan, elevations) and assess historic‑resource impacts; if the property is listed, avoid exterior work that would cause an adverse impact. § 10-6.302(g)
• If seeking higher FAR/density or lot split options, verify whether Table 4A exceptions or urban‑lot‑split pathways exclude the parcel because of historic status. § 10-3.402 note; § 10-4.309
• Budget for public hearings and consultant fees (the Town may require an outside historic architect and charge applicant). § 10-3.2103(d)

Risks & Ambiguities

Plain‑English summary

If your property is on San Anselmo’s local historic list or inside a Town historic district, expect stricter limits on demolition, special design‑review scrutiny for exterior changes, possible ineligibility for certain lot‑split/density incentives, and extra ADU constraints to avoid harming historic significance; all of this is grounded in the local zoning code’s demolition article (§ 10-3.2101 et seq.), design‑review article (§ 10-3.1501 et seq.), the ADU chapter (§ 10-6.301 et seq.), and Table 4A development notes.

Source References

• San Anselmo Municipal Code — Demolition Permit: § 10-3.2101–10-3.2105 (Demolition permit purpose, thresholds, submittal requirements, findings).
• San Anselmo Municipal Code — Design Review: § 10-3.1501–10-3.1506, § 10-3.1504–10-3.1505 (triggers, review authority, findings for R-1-H, R-1-C, R-3, etc.).
• San Anselmo Municipal Code — Development Standards / Table 4A note: § 10-3.402 and Table 4A notes (FAR/density exception for historic sites).
• San Anselmo Municipal Code — ADUs (Chapter 6): § 10-6.301–10-6.304 (objective ADU standards; ADU historic clause; parking exemptions for historic districts).
• San Anselmo Municipal Code — Urban lot split / two‑unit development exclusions: § 10-4.309, § 10-4.408.
• San Anselmo Municipal Code — Setback & height / ridge zone: § 10-3.404(b) (18 ft above ridgeline rule for R-1-H/R-1-C/R-1).
• California Building Standards Code (Title 24) — historic‑structure variances (for context where building‑code variances intersect preservation).
• State ADU guidance (context on historic ADU rules): 2025 California ADU handbook (state law interaction).

Retrieved passages

• San Anselmo Zoning Code (article does) High relevance show source text
• San Anselmo Zoning Code (Title 4) Medium relevance show source text
• San Anselmo Zoning Code (Chapter 12.75) Medium relevance show source text
• San Anselmo Zoning Code (Section 10-3.1404) Medium relevance show source text
• San Anselmo Zoning Code (Section 10-3.404) Medium relevance show source text
• San Anselmo Zoning Code (Section 10-3.1601) Medium relevance show source text
• San Anselmo Zoning Code (Section 10-3.1506) Medium relevance show source text
• San Anselmo Zoning Code (§ 1) Medium relevance show source text
• San Anselmo Zoning Code (Section 5020.1) Medium relevance show source text
• San Anselmo Zoning Code (§ 1) Medium relevance show source text
• San Anselmo Zoning Code (Section 10-3.1506) Medium relevance show source text
• San Anselmo Zoning Code (Title 4) Medium relevance show source text
• San Anselmo Zoning Code (§ 2) Medium relevance show source text
• San Anselmo Zoning Code (§ 2) Medium relevance show source text
• San Anselmo Zoning Code (Chapter and) Medium relevance show source text

Cited sections

• San Anselmo Municipal Code — Demolition Permit: **§ 10-3.2101–10-3.2105** (Demolition permit purpose, thresholds, submittal requirements, findings). (§ 10-3.2101)
• San Anselmo Municipal Code — Design Review: **§ 10-3.1501–10-3.1506**, **§ 10-3.1504–10-3.1505** (triggers, review authority, findings for R-1-H, R-1-C, R-3, etc.). (§ 10-3.1501)
• San Anselmo Municipal Code — Development Standards / Table 4A note: **§ 10-3.402** and Table 4A notes (FAR/density exception for historic sites). (§ 10-3.402)
• San Anselmo Municipal Code — ADUs (Chapter 6): **§ 10-6.301–10-6.304** (objective ADU standards; ADU historic clause; parking exemptions for historic districts). (Chapter 6)
• San Anselmo Municipal Code — Urban lot split / two‑unit development exclusions: **§ 10-4.309**, **§ 10-4.408**. (§ 10-4.309)
• San Anselmo Municipal Code — Setback & height / ridge zone: **§ 10-3.404(b)** (18 ft above ridgeline rule for R-1-H/R-1-C/R-1). (§ 10-3.404)
• California Building Standards Code (Title 24) — historic‑structure variances (for context where building‑code variances intersect preservation). (Title 24)
• State ADU guidance (context on historic ADU rules): 2025 California ADU handbook (state law interaction).
• SanAnselmo_ZoningCode.md
• 2025 California Building Code.md
• 2025 California ADU handbook.md

• Official San Anselmo code library