Urban Planning Área Unidades
Blocks, Lots, e Densidade Measures
Learn Planning UnidadesUrban planners, developers, e zoning officials use specialized area medições to regulate development, calculate density, e manage city growth. Understanding estes unidades—from city blocks to floor area ratios—helps interpret zoning codes e development plans.
City Block Sizes
"City block" varies significantly by city:
| City | Typical Block Size | Área |
|---|---|---|
| Manhattan (padrão) | 250' × 900' (N-S) ou 250' × 250' (E-W) | 5.7 acres |
| Portland, OR | 200' × 200' | 0.92 acres |
| Chicago (padrão) | 330' × 660' | 5.0 acres |
| Salt Lake City | 660' × 660' | 10 acres |
| Barcelona (Eixample) | 113m × 113m | 1.28 hectares |
| Melbourne CBD | 100m × 200m | 2.0 hectares |
Nota: Blocks often vary within o mesmo city.
Lot Size Standards
US Residential Zoning
| Zone Type | Typical Minimum Lot | Área |
|---|---|---|
| High-density urban | 2,000-3,000 sq ft | 0.05-0.07 acres |
| Urban residential | 5,000-6,000 sq ft | 0.11-0.14 acres |
| Suburban (padrão) | 7,000-10,000 sq ft | 0.16-0.23 acres |
| Suburban (larger) | 0.25-0.5 acres | 10,890-21,780 sq ft |
| Semi-rural | 1-2 acres | 43,560-87,120 sq ft |
| Rural residential | 5-10 acres | 217,800-435,600 sq ft |
Floor Área Ratio (FAR)
FAR controls building size relative to lot size:
FAR Calculation
FAR = Total building floor area ÷ Lot area
FAR Examples
| FAR | 10,000 sq ft lot allows | Typical Usar |
|---|---|---|
| 0.5 | 5,000 sq ft building | Single-family suburban |
| 1.0 | 10,000 sq ft building | Low-rise residential |
| 2.0 | 20,000 sq ft building | Mid-rise mixed use |
| 5.0 | 50,000 sq ft building | Urban commercial |
| 10.0 | 100,000 sq ft building | Downtown high-rise |
| 15.0+ | 150,000+ sq ft building | Dense urban core |
Densidade Measurements
Residential Densidade
| Densidade Type | Unidades per Acre | Unidades per Hectare |
|---|---|---|
| Rural | 0.1-1 | 0.25-2.5 |
| Suburban (low) | 1-4 | 2.5-10 |
| Suburban (padrão) | 4-8 | 10-20 |
| Urban (low-rise) | 15-30 | 37-74 |
| Urban (mid-rise) | 30-75 | 74-185 |
| Urban (high-rise) | 75-200+ | 185-500+ |
Population Densidade
- Low density: <5,000 people/sq mile
- Medium density: 5,000-15,000/sq mile
- High density: 15,000-50,000/sq mile
- Muito high: >50,000/sq mile
Commercial/Industrial Unidades
Office Space
- Per employee: 150-300 sq ft (14-28 sq m) typical
- Post-COVID trend: 200-400 sq ft per employee
Retail Space
- Small retail: 1,000-5,000 sq ft (93-465 sq m)
- Big box: 50,000-200,000 sq ft (4,645-18,580 sq m)
Industrial/Warehouse
- Small: 10,000-50,000 sq ft
- Medium: 50,000-200,000 sq ft
- Large distribution: 500,000-1,000,000+ sq ft
Lot Coverage e Abrir Space
Lot Coverage Ratio
Lot coverage = Building footprint ÷ Lot area
| Zone Type | Typical Max Coverage |
|---|---|
| Single-family residential | 30-50% |
| Multi-family residential | 50-70% |
| Commercial | 70-90% |
| Industrial | 50-80% |
Abrir Space Requirements
Muitos codes require minimum open space:
- Private open space: 60-100 sq ft per unidade
- Comuns open space: 100-200 sq ft per unidade
- Parks padrão: 10 acres per 1,000 residents
Conclusão
Urban planning uses specialized area medições to control development density e form. Floor Área Ratio (FAR) limits total building size relative to lot size. Densidade measures unidades ou people per acre/hectare. Understanding estes metrics helps interpret zoning regulations e development potential—whether you're a developer, homeowner, ou community member.