Corte Madera — Nonconforming Uses

Last reviewed: July 1, 2026

Overview

This page summarizes how the Town of Corte Madera treats nonconforming uses, nonconforming structures, and nonconforming sites under the local zoning ordinance (Title 18). It is a plain‑English synthesis of the town's rules on continuation, repair, enlargement, abandonment, restoration after damage, and forced elimination of nonconformities, with district-by-district context for decision‑relevant standards. Always verify parcel‑specific determinations with the Planning Department. Key definitions and procedures are contained in Chapter 18.32 of the municipal code. § 18.32.010 .

What the Corte Madera code says (core rules)

• Definition / purpose: A nonconforming use/structure is one lawfully established before a change in the ordinance that no longer complies with current district regulations; Chapter 18.32 states the purpose is to allow limited continuation while phasing nonconformities out over time. § 18.32.010 .
• Continued use and maintenance: Existing nonconforming uses and structures may be continued and are eligible for routine maintenance and repair. § 18.32.020 .
• No enlargement or lateral extension: A nonconforming use may not be enlarged or extended to occupy additional structure or site area beyond what it occupied on the date it became nonconforming. § 18.32.030 .
• Alterations to structures: A nonconforming structure may not be moved, altered, enlarged or reconstructed in a way that increases its nonconformity with coverage, yards or height requirements. § 18.32.040 .
• Change of use: A nonconforming use cannot be changed to a different nonconforming use. § 18.32.050 .
• Abandonment threshold: If a nonconforming use or the structure housing it is discontinued/unoccupied for a continuous period of 90 days, the nonconforming right is lost and any subsequent use must conform to current district rules. § 18.32.060 .
• Restoration after damage/destruction: If damaged to 50% or less of its value, a nonconforming structure and use may be restored if work starts within one year and proceeds diligently (unless the Planning Commission extends the time). If damaged more than 50%, it may not be restored except in full compliance with current regulations. § 18.32.070(a) .
• Elimination categories and timeframes: Certain nonconforming uses must be removed within prescribed periods measured from the ordinance effective date—examples include unbuilt uses (5 years) and specific commercial late‑night uses (1 year unless a CUP is obtained). § 18.32.080 .
• Low‑value structures: A structure with fair market value under $2,000 that violates district dimensional/sign standards must be removed within three years unless altered to comply. § 18.32.090 .
• When nonconformity starts: If a change of zoning or district regulations creates the nonconformity, the elimination clock runs from the effective date of that change. § 18.32.100 .
• Nonconforming lots: A lot that is legally created but has dimensions smaller than current minimums may still be used for a permitted use, subject to other district regulations. § 18.32.110 .
• Appeals and interpretations: Administrative interpretations by the Planning Director (including on nonconforming status) may be appealed to the Planning Commission. § 18.34.010 .
• The general requirement to conform: Except where Chapter 18.32 applies, every site/structure must conform to its district regulations (yards, coverage, etc.). § 18.24.020 .

(If you need the raw ordinance text, see Chapter 18.32 in the Corte Madera zoning code: § 18.32.010–§ 18.32.110).

District-by-district breakdown (where these rules matter)

Below are the Corte Madera districts most frequently involved in nonconforming‑use questions. Each subsection lists the district purpose, typical permitted uses, and the dimensional / development standards an applicant will compare against when evaluating whether a structure or use is nonconforming.

Note: first mention of key related permit topics below are linked: development standards, parking, design review, Overlay Districts, ADUs, California Building Standards Code.

R-1 — Medium‑Density Residential (18.08.200–220)

• Purpose: Implements residential policies for medium‑density neighborhoods; rules are modified by overlay districts where applicable. § 18.08.200 .
• Typical permitted uses: single‑family dwellings, accessory structures, home occupations, small day care, limited residential care facilities (see use tables). § 18.08.020 (permits list) .
• Key standards: minimum lot area 7,500 sf, front setback 20 ft (>=7,500 sf) or 15 ft (<7,500 sf), side yards 5–6 ft (depending on lot size), max height 30 ft, lot coverage and FAR are in the R‑district tables. § 18.08.210–220; Table 1. .
• Where it applies: Most single‑family neighborhoods shown on the Official Zoning Map; design review applies to projects per § 18.08.050. § 18.08.050 .

R-1‑A — Low‑Density Residential (18.08.300–320)

• Purpose & uses: Large‑lot single‑family neighborhoods; similar permitted uses as R‑1 but lower density. § 18.08.300–310 .
• Key standards: minimum lot area 20,000 sf, front yard 25 ft, side yards 10 ft (permitted uses), rear yard 35 ft, coverage 25%, height 30 ft, and detailed FAR rules in § 18.08.320(g). § 18.08.320 .

R-1‑B (Very Low) and R-1‑C (Open Residential)

• Purpose & uses: Larger lots / open residential with stricter setbacks and lower unit/acre standards — see Table 1 for numeric values such as front/rear/side setbacks, coverage, height. Table 1 (Residential Zoning District Development Standards) provides a side‑by‑side comparison. Table 1 (18.08.*) .

R-2 / R-3 — Multiple Dwelling Districts

• Purpose: Allow multi‑unit housing at specified densities; R‑2 and R‑3 have separate lot area per unit, setbacks and coverage rules. See § 18.08.100–110 (R‑2) and § 18.08.600–620 (R‑3). § 18.08.100–110 ; § 18.08.600–620 .
• Key standards: R‑2 minimum site area 8,000 sf (frontage/width rules apply), R‑3 density and minimum area per dwelling unit (e.g., 2,460 sf/unit) plus max height commonly 30–35 ft and coverage caps in Table 1. § 18.08.110; § 18.08.620; Table 1.

C-1 — Local Commercial (18.12.100–155)

• Purpose: Provide local‑serving retail and services that don’t create impacts incompatible with nearby residences. § 18.12.100 .
• Typical permitted uses: small retail shops, personal services, restaurants (without drive‑through), offices configured for local shopping centers (see 18.12.). § 18.12. (C‑1 rules) .
• Key standards: front yard minimum 10 ft (more where adjacent to residential), height limit 30 ft, FAR 34%, landscaped buffer rules, parking per the off‑street parking chapter. § 18.12.115–140; parking chapter § 18.20. .
• Nonconforming notes: Certain late‑night commercial uses in C‑1 were singled out in elimination schedules — see § 18.32.080(b)(2). § 18.32.080(b)(2) .

MX‑1 — Mixed Use (Tamal Vista Corridor)

• Purpose: Implement mixed residential/nonresidential development guidance for Tamal Vista area; includes special FAR/height provisions that affect whether a structure is nonconforming. § 18.13.100 ff. .
• Nonconforming evaluation: Compare existing build to MX‑1 floor area, height and specific design findings when a use was legal under prior zoning but differs from current MX‑1 standards. § 18.13.* .

W — Waterbodies / Waterways (18.16.400–410)

• Purpose: Apply to San Francisco Bay, Corte Madera and San Clemente creek areas; limited permitted uses (water‑borne recreational uses etc.) and conditional uses require use permits. § 18.16.400–410 .
• Nonconforming implications: A prior upland structure that now falls within prohibited uses or dimensional rules may be rendered nonconforming; elimination/repair rules in Chapter 18.32 control. § 18.32.010–110 .

Quick reference table — decision‑relevant standards & common nonconforming triggers

Checklist — what an applicant must satisfy / check when a property might be nonconforming

• Confirm the date of original establishment vs the date of the zoning/regulation change that triggered nonconforming status (establish the baseline). § 18.32.100
• Determine whether the use or structure is a legal pre‑existing use/structure (document permits, deeds, recorded maps). § 18.32.010–020
• Measure the current discrepancies (setbacks, coverage, height, sign area, FAR) using the district standards in Table 1 and applicable district sections. § 18.08.* (Table 1)
• For proposed repairs or reconstruction, calculate percentage damage (value or floor‑area ratio) per § 18.32.070(c) and get Planning Director review for the valuation method used. § 18.32.070(c)
• Confirm whether any proposed alteration would “increase the discrepancy” under § 18.32.040 — if so, the alteration is prohibited. § 18.32.040
• If the use was discontinued, verify continuous vacancy for 90 days to assess abandonment. § 18.32.060
• Check whether the nonconforming use/structure falls in a category scheduled for early elimination (e.g., unbuilt uses, certain loudspeaker/signs, late‑night C‑1 uses). § 18.32.080
• If considering an ADU, check local ADU procedures but note ADU‑specific state rules that may interact with nonconforming zoning — verify with the Planning Division. § 18.31.* (ADU chapter) — local ministerial ADU rules.

Risks & Ambiguities

If a question cannot be answered from the municipal code as written, note: "Verify with the jurisdiction."

Plain‑English summary

If your Corte Madera property was legal under an older zoning rule but now doesn’t match the zone, Chapter 18.32 says you may generally keep using and maintaining it — but you cannot expand it, change it to a different nonconforming use, or rebuild it after major destruction unless you comply with current rules. Simple repairs are allowed; long vacancies, large destruction (over 50%), and specific low‑value items are subject to strict removal or compliance deadlines. § 18.32.010–110

Source References

• Corte Madera Municipal Code — Chapter 18.32, Nonconforming Uses, Structures and Sites: § 18.32.010–§ 18.32.110.
• Corte Madera zoning district standards and Table 1 (Residential Zoning District Development Standards): § 18.08.200–§ 18.08.320 and Table 1.
• R‑2 and R‑3 district standards: § 18.08.100–§ 18.08.110 and § 18.08.600–§ 18.08.620.
• C‑1 Local Shopping District standards and purpose: § 18.12.100–§ 18.12.145.
• Off‑street parking standards (used for evaluating nonconforming parking): Chapter 18.20.
• General provisions (conformity with district regulations): § 18.24.020.
• Appeals of administrative determinations (re: Planning Director interpretations): Chapter 18.34 / § 18.34.010.
• Corte Madera ADU procedures (may intersect with nonconforming zoning issues): Chapter 18.31.

Retrieved passages

• Corte Madera Zoning Code (Chapter 18.32) High relevance show source text
• Corte Madera Zoning Code (§ 3) High relevance show source text
• Corte Madera Zoning Code (§ 3) High relevance show source text
• Corte Madera Zoning Code (§ 3) High relevance show source text
• Corte Madera Zoning Code (Section 18.20.100) High relevance show source text
• Corte Madera Zoning Code (Section 65943.) High relevance show source text
• Corte Madera Zoning Code (Chapter 18.31) High relevance show source text
• Corte Madera Zoning Code (§ 3) High relevance show source text
• CFC § 4 (§ 4) Medium relevance show source text
• Corte Madera Zoning Code (Section 18.24.080) Medium relevance show source text
• Corte Madera Zoning Code (Section 18.32.110.) Medium relevance show source text
• Corte Madera Zoning Code (§ 3) Medium relevance show source text
• Corte Madera Zoning Code (§ 1) Medium relevance show source text
• Corte Madera Zoning Code (§ 3) Medium relevance show source text
• CBC § 18.31 (Section 18.31A.050) Medium relevance show source text
• Corte Madera Zoning Code (§ 66314) Medium relevance show source text
• Corte Madera Zoning Code (§ 66333) Medium relevance show source text
• CBC § 66321 (§ 66321) Medium relevance show source text
• Corte Madera Zoning Code (Chapter 18.21) Medium relevance show source text
• Corte Madera Zoning Code (§ 3) Medium relevance show source text
• CFC § 4 (§ 4) Medium relevance show source text
• CBC § 100 Medium relevance show source text
• Corte Madera Zoning Code (Chapter 18.02) Medium relevance show source text

Cited sections

• Corte Madera Municipal Code — Chapter 18.32, Nonconforming Uses, Structures and Sites: **§ 18.32.010–§ 18.32.110**. (Chapter 18.32)
• Corte Madera zoning district standards and Table 1 (Residential Zoning District Development Standards): **§ 18.08.200–§ 18.08.320** and Table 1. (§ 18.08.200)
• R‑2 and R‑3 district standards: **§ 18.08.100–§ 18.08.110** and **§ 18.08.600–§ 18.08.620**. (§ 18.08.100)
• C‑1 Local Shopping District standards and purpose: **§ 18.12.100–§ 18.12.145**. (§ 18.12.100)
• Off‑street parking standards (used for evaluating nonconforming parking): **Chapter 18.20**. (Chapter 18.20)
• General provisions (conformity with district regulations): **§ 18.24.020**. (§ 18.24.020)
• Appeals of administrative determinations (re: Planning Director interpretations): **Chapter 18.34 / § 18.34.010**. (Chapter 18.34)
• Corte Madera ADU procedures (may intersect with nonconforming zoning issues): **Chapter 18.31**. (Chapter 18.31)
• CorteMadera_ZoningCode.md

• Official Corte Madera code library