Redwood City — Historic Preservation

Last reviewed: July 2, 2026

Overview

This page summarizes what the Redwood City Zoning Ordinance currently says about historic preservation: who reviews historic resources, where historic-resource protections affect zoning and development standards, and the specific code triggers that commonly affect projects (e.g., ADUs, SB 9 projects, and large redevelopment). For department procedures such as landmark nominations, demolition-delay processes, and Mills Act contracts that are not spelled out in the excerpts provided, verify with the City — those specifics are Not found in retrieved materials. For general zoning context see the Redwood City zoning & planning overview.

Key takeaways up front:

• The city maintains a Historic Resources Advisory Commission and assigns review roles to planning bodies (§ 40.4, § 40.6) .
• Properties listed on the California Register are required to follow the Secretary of the Interior’s treatment standards for certain work (notably accessory dwelling units) § 37.3(H) .
• Some objective development standards change when a site is within or adjacent to an identified historic resource (e.g., stepback/daylight plane rules in § 54.7 and § 55.3) .
• An SB 9 ministerial project is prohibited on parcels inside a historic district or on parcels listed on state/local historic registers § 32.5(E) .

Note on links in this page: when the topic naturally mentions practical procedures you may need, follow the linked pages for related operational rules — for example, consult the city's Development Standards for dimensional rules, the Design Review page for architectural review process, the Parking page for parking requirements, the Overlay Districts page for combining/overlay rules, the ADUs page for accessory dwelling specifics, and the California Building Standards Code for state code crosswalks.

How the Zoning Ordinance handles historic resources (summary of controlling rules)

• Review bodies and advisory structure: The Planning Commission appoints members to historic advisory groups and the City’s administrative structure includes a specific Historic Resources Advisory Commission; duties and appointment authority are assigned under § 40.4 and § 40.6 .
• ADU-specific historic requirement: When an ADU is proposed on a property listed in the California Register of Historical Resources, the project must comply with the applicable Secretary of the Interior standards § 37.3(H) . See the ADU rules for other objective development standards ADUs.
• Project siting next to historic resources: For certain mixed-use districts, upper-story stepbacks and an inward 45-degree daylight plane are required where a property abuts a public open space or an historic resource § 54.7(B)(2) and § 55.3 .
• SB 9 limits: An SB 9 (ministerial two-lot / duplex) project is explicitly prohibited on sites that are in a historic district or listed on state/local historic registers § 32.5(E)(3) .
• Where historic protections intersect discretionary relief: waivers or density-bonus concessions must avoid adverse impacts on properties listed in the California Register; a waiver may be denied if it would adversely impact such a resource § 32.19(C)(2–3) .

If a term below is used in practice (design review, parking, variances), consult the linked rule page (e.g., Design Review, Parking, Variances and Exceptions) because the zoning ordinance routes many historic-related changes through those review processes.

District-by-district breakdown (how preservation rules interact with key districts)

Important: each district subsection below lists the district purpose, typical permitted uses, the code elements that most commonly interact with historic-preservation concerns, and where the district applies. All statements are grounded in the cited ordinance sections.

MUN (Mixed‑Use Neighborhood)

• Purpose: The MUN district is intended for mixed-use neighborhood development with specific building, site, and open-space standards § 54.1 .
• Typical permitted uses: Mixed residential and commercial (see Table 54‑1) — residential, retail, personal services, small offices § 54.2 .
• Key dimensional standards that matter for historic adjacency: Maximum heights and FAR limits (Table 54‑3) include maximum height for residential and commercial uses and FAR limits; upper-story 45-degree daylight plane protections apply adjacent to an historic resource § 54.7(B) (Table 54‑3) .
• Where it applies: geographic boundaries for Article 54 developments; Article 54 provisions supersede other maritime zoning where they conflict § 54.1(B) .

MUC-SB (Mixed‑Use Corridor — Streetcar Broadway sub‑district)

• Purpose: The MUC‑SB sub‑district recognizes Broadway’s historic buildings and requires new construction to be respectful of existing historic structures in scale and design § 53.2(D)(d) .
• Typical uses: commercial, hospitality, mixed-use that supports street-level activation § 53.2 .
• Preservation implications: special orientation, façade articulation, and entrance-frequency standards are required so new work is compatible with nearby historic buildings § 53.8 (supplemental standards) .
• Where it applies: Broadway corridor and adjacent parcels covered in Article 53; check the Downtown precise plan for additional Downtown rules and notice requirements § 41.5 .

IP (Industrial‑Park)

• Purpose: IP supports large administrative, research, and industrial campus-style development § 18.1 .
• Typical permitted uses: offices, R&D, light manufacturing and warehousing § 18.2 .
• Preservation interactions: While IP is not a typical historic-district area, any development adjacent to an identified historic resource must respect the city’s general protections (e.g., daylight plane and design review when required) § 54.7(B), § 55.3 .
• Where it applies: industrial park-zoned land across the city as described in Article 18 § 18.1–18.2 .

R-1 (Residential — Single‑Family)

• Purpose: R-1 promotes detached single-family living and allows accessory dwellings § 5.1 .
• Typical permitted uses: single-family homes and related accessory uses; ADUs allowed under Article 37 § 5.2; § 37.1–37.3 .
• Key numeric standards: maximum height 28 ft / 2.5 stories, minimum lot width 50 ft, lot coverage 40%, front setback 15 ft, rear setback 20 ft, pervious area minima (e.g., 40% of lot) — see § 5.4–5.9 for details § 5.6, § 5.4–5.5, § 5.9 .
• Preservation implications: R‑1 properties that are historic or inside a historic district are subject to the same ADU historic-preservation rule (Secretary standards) § 37.3(H) and SB 9 limitations § 32.5(E) .
• Where it applies: single-family neighborhoods generally in the western portions of the city § 5.1(B) .

R-2 (Residential — Duplex)

• Purpose & uses: R-2 is intended for duplex and small-scale residential development; includes accessory dwelling provisions § 6.1–6.2 .
• Key numeric standards: maximum height 28 ft, pervious requirements (e.g., 40%), front setback 15 ft, rear 20 ft § 6.3, § 6.7, § 6.9 .
• Preservation implications: same as R‑1 where a parcel is designated or eligible as a historic resource (ADU Secretary standards; SB 9 prohibition) § 37.3(H), § 32.5(E) .

Quick reference table — decision‑relevant historic-preservation items

Checklist (what an applicant must check / provide for projects touching historic resources)

• Confirm whether the parcel is designated/listed as a historic resource (city/local register or California Register). Verify with the Planning Division (Verify with the jurisdiction). Relevant: § 32.5(E) .
• If the property is listed on the California Register, prepare work to meet the Secretary of the Interior’s Standards for treatment where required (notably ADUs) § 37.3(H) .
• For projects in MUN, Downtown/MUC‑SB, or other Article 53/54/55 areas, test building massing against the 45‑degree daylight plane and upper‑story stepback requirement where adjacent to an historic resource § 54.7(B)(2); § 55.3 .
• Determine whether the project will be ministerial (e.g., SB 9, some ADUs) or discretionary (requires design or use permits) and route submittal to the appropriate review authority per Article 41 § 41.4–41.6 .
• If requesting a waiver or density bonus, include a historic‑resource analysis to demonstrate no adverse impact to registered resources § 32.19 .
• Prepare materials for the Historic Resources Advisory Commission or Planning Commission if the project or designation requires advisory review § 40.4(E); § 40.6 .
• For ADU projects, include required objective development standard compliance (size/parking/pervious area) and the historic‑treatment documentation if listed § 37.3 .
• Consult Design Review and Development Standards for objective design rules and submittal checklists; consult Parking for parking exceptions related to ADUs.

Risks & Ambiguities

Plain‑English Summary

If your house or lot is listed on a historic register or sits inside a historic district, Redwood City’s zoning rules add extra checks: ADUs on such properties must follow the Secretary of the Interior’s Standards § 37.3(H); SB 9 ministerial splits are blocked on historic lots § 32.5(E); and in some downtown or mixed‑use districts new buildings must step back and obey a 45‑degree daylight plane near historic resources § 54.7(B)(2); § 55.3. The Planning Commission and the Historic Resources Advisory Commission are the city bodies that handle historic review and advice § 40.4; § 40.6 — contact Planning early to verify a property’s historic status and the exact review path (Verify with the jurisdiction) .

Source References

• § 40.4, § 40.6 — Planning Commission duties and Historic Resources Advisory Commission powers (appointments and advisory role) .
• § 37.3(H) — Accessory Dwelling Units: historic‑property requirement — Secretary of the Interior’s Standards for properties listed in the California Register .
• § 32.5(E) — SB 9 eligibility and prohibition when a site is within a historic district or listed on state/local registers .
• § 54.7 (Table 54‑3) — MUN district heights, FAR, and upper‑story stepback adjacent to historic resources § 54.7(B)(2) .
• § 55.3 — Mixed‑Use Transitional district: 45‑degree daylight plane and stepback adjacent to historic resources .
• Article 18 (IP district) — Purpose and permitted uses for Industrial Park district § 18.1–18.2 .
• Article 5 (R‑1 / RH) — Single‑family district purposes and numeric standards (height, setbacks, lot width, lot coverage, pervious area) § 5.1–5.9 .
• Article 6 (R‑2) — Duplex district standards (height, setbacks, pervious area) § 6.1–6.9 .
• Zoning common procedures and review authorities: Article 41 (application review, review authorities, appeals) § 41.3–41.6 .
• Article references and tables cited above are from the Redwood City Zoning Code excerpts supplied (city looseleaf supplements). For related operational topics (design review, parking, overlays, ADU implementation details) consult the site links embedded in the body such as Design Review, Parking, Overlay Districts, ADUs, and Development Standards.

Retrieved passages

• Redwood City Zoning Code (Article 41) High relevance show source text
• CBC § 32.12 (Section 32.12) High relevance show source text
• CFC § 3 (Section 66333) High relevance show source text
• Redwood City Zoning Code (Section 39.3.) High relevance show source text
• Redwood City Zoning Code Medium relevance show source text
• Redwood City Zoning Code (Section number) Medium relevance show source text
• Redwood City Zoning Code (Chapter 1) Medium relevance show source text
• Redwood City Zoning Code (Section 54.7.B) Medium relevance show source text
• Redwood City Zoning Code (§ 2.21.2) Medium relevance show source text
• Redwood City Zoning Code Medium relevance show source text
• CBC § 51179 (Section 51179) Medium relevance show source text
• Redwood City Zoning Code Medium relevance show source text
• Redwood City Zoning Code (Section 55.3.3) Medium relevance show source text
• Redwood City Zoning Code (Section 32.19) Medium relevance show source text
• CBC § 4 (Chapter 12.75) Medium relevance show source text
• Redwood City Zoning Code (§ 4) Medium relevance show source text
• Redwood City Zoning Code (Section 32.3) Medium relevance show source text
• Redwood City Zoning Code (§ 4) Medium relevance show source text
• Redwood City Zoning Code Medium relevance show source text
• Redwood City Zoning Code (§ 4) Medium relevance show source text
• Redwood City Zoning Code Medium relevance show source text
• Redwood City Zoning Code (Section apply) Medium relevance show source text
• Redwood City Zoning Code (§ 5) Medium relevance show source text

Cited sections

• **§ 40.4**, **§ 40.6** — Planning Commission duties and Historic Resources Advisory Commission powers (appointments and advisory role) . (§ 40.4)
• **§ 37.3(H)** — Accessory Dwelling Units: historic‑property requirement — Secretary of the Interior’s Standards for properties listed in the California Register . (§ 37.3)
• **§ 32.5(E)** — SB 9 eligibility and prohibition when a site is within a historic district or listed on state/local registers . (§ 32.5)
• **§ 54.7 (Table 54‑3)** — MUN district heights, FAR, and upper‑story stepback adjacent to historic resources **§ 54.7(B)(2)** . (§ 54.7)
• **§ 55.3** — Mixed‑Use Transitional district: 45‑degree daylight plane and stepback adjacent to historic resources . (§ 55.3)
• **Article 18 (IP district)** — Purpose and permitted uses for Industrial Park district **§ 18.1–18.2** . (Article 18)
• **Article 5 (R‑1 / RH)** — Single‑family district purposes and numeric standards (height, setbacks, lot width, lot coverage, pervious area) **§ 5.1–5.9** . (Article 5)
• **Article 6 (R‑2)** — Duplex district standards (height, setbacks, pervious area) **§ 6.1–6.9** . (Article 6)
• Zoning common procedures and review authorities: **Article 41** (application review, review authorities, appeals) **§ 41.3–41.6** . (Article 41)
• Article references and tables cited above are from the Redwood City Zoning Code excerpts supplied (city looseleaf supplements). For related operational topics (design review, parking, overlays, ADU implementation details) consult the site links embedded in the body such as Design Review, Parking, Overlay Districts, ADUs, and Development Standards. (Article references)
• RedwoodCity_ZoningCode.md

• Official Redwood City code library