Ch4. Zoning and Land Use Regulation — Understanding How Land Is Controlled

The US Land Use Planning Framework

Zoning: A police-power regulation enacted by local governments to control how land is used. Zoning ordinances are adopted under authority delegated by state enabling statutes.

Land Use Planning Hierarchy (US):
Federal (environmental law, Fair Housing Act)
  → State (general plan / comprehensive plan enabling statutes)
    → County / City General Plan (long-range vision)
      → Zoning Ordinance (legally binding land use rules)
        → Specific Plans / Overlay Districts (site-level rules)

Zoning Classification System

Standard zoning categories used across US municipalities:

Zoning Districts
├── Residential (R)
│   ├── R-1: Single-family detached
│   ├── R-2: Two-family / duplex
│   ├── R-3: Low-density multifamily
│   └── R-4+: Medium/high-density multifamily
├── Commercial (C)
│   ├── C-1: Neighborhood commercial
│   ├── C-2: General commercial
│   └── C-3: Heavy commercial / regional retail
├── Industrial (I / M)
│   ├── I-1: Light industrial
│   └── I-2: Heavy industrial
├── Agricultural (A)
└── Special Purpose (SP) — schools, parks, government

Building Coverage Ratio and Floor Area Ratio

Building Coverage Ratio (Lot Coverage)

Lot Coverage = Building Footprint ÷ Lot Area × 100%

How much of the lot surface can be covered by the building footprint.

Zone	Typical Lot Coverage Limit
Single-family residential	35–50%
Multifamily residential	50–60%
Commercial	70–90%
Industrial	60–75%
Open space / agricultural	5–10%

Floor Area Ratio (FAR)

FAR = Total Floor Area ÷ Lot Area
(Parking garages and basements may be excluded depending on local code)

Controls building density — how much total floor space can be built on a given lot.

Zone	Typical FAR
Single-family residential	0.5–1.0
Low-rise multifamily	1.0–2.5
Mixed-use / mid-rise	2.0–5.0
Downtown / CBD	5.0–15.0+

Residential Zone Subtypes

Zone	Description
R-1 (Single-family exclusive)	Detached single-family homes only; no duplexes or apartments
R-2 (Two-family)	Duplexes permitted
R-3 (Low-density multifamily)	Small apartment buildings (3–4 units)
R-4 / RM (Multifamily)	Larger apartment complexes; may allow mixed residential use
Mixed-use residential	Residential + ground-floor commercial permitted

Development Approvals and Permits

Types of development approvals:

Building Permit: Required for new construction, additions, and major alterations
Use Permit / Conditional Use Permit (CUP): For uses allowed in a zone only with additional conditions
Variance: Permission to deviate from specific zoning standards (setbacks, height, FAR)
Rezoning: Change the zoning classification of a parcel — requires public hearing

Review criteria for discretionary permits: consistency with general plan, infrastructure capacity, environmental impact (CEQA/NEPA), neighborhood compatibility.

Lot Coverage (Building Coverage Ratio) ★★★★★ : Building footprint divided by lot area. Controls how much of the ground a structure can occupy horizontally. Memory tip: Lot coverage = horizontal density

FAR (Floor Area Ratio) ★★★★★ : Total floor area divided by lot area. Controls building density — a higher FAR allows taller or larger buildings. Memory tip: FAR = vertical/total density

Zoning Classifications ★★★★★ : R (residential), C (commercial), I/M (industrial), A (agricultural), SP (special purpose). Local ordinances add subdistricts (R-1, C-2, etc.). Memory tip: R-C-I-A — Residential, Commercial, Industrial, Agricultural

Practice Quiz

Q. A lot is 10,000 sq ft. The zoning allows 50% lot coverage and 2.0 FAR. What is the maximum building footprint and the maximum total floor area?

Maximum footprint = 10,000 × 50% = 5,000 sq ft. Maximum total floor area = 10,000 × 2.0 = 20,000 sq ft.

Q. What is the difference between a variance and a rezoning?

A variance grants relief from specific dimensional standards (setbacks, height limits) without changing the underlying zoning classification. A rezoning changes the zoning category of a parcel entirely — a much larger action that requires a general plan amendment if the two conflict.