# Parking Design

## Surface Parking Layout

### Stall Dimensions
| Type | Width | Length | Notes |
|------|-------|--------|-------|
| Standard | 9' | 18' | Most common |
| Compact | 8' | 16' | Check jurisdiction limit |
| Large/premium | 9'-6" | 20' | Suburban, retail |
| Accessible | 8' + 5' aisle | 18' | See ADA section |
| Van accessible | 8' + 8' aisle | 18' | Required ratio |
| Parallel | 8' | 22' | On-street, roadway |

### Aisle Widths
| Parking Angle | One-Way | Two-Way |
|---------------|---------|---------|
| 90° | 24' | 24' |
| 75° | 21' | 22' |
| 60° | 18' | 20' |
| 45° | 13' | 20' |
| 30° | 11' | 18' |
| 0° (parallel) | 12' | 20' |

### Module Widths (Total)
| Angle | One-Way | Two-Way |
|-------|---------|---------|
| 90° | 60'-62' | 60'-62' |
| 60° | 54'-56' | 56'-58' |
| 45° | 48'-50' | 54'-56' |

---

## Parking Structure Design

### Ramp Types
| Type | Slope | Efficiency | Notes |
|------|-------|------------|-------|
| Straight | 5%-6.67% | Medium | Simple, long |
| Helix (circular) | 5%-6% | High | Continuous flow |
| Speed ramp | 12%-15% | High | No parking on ramp |
| Express ramp | 12%-15% | High | One-way up/down |
| Split-level | 5%-6% | High | Half-floor circulation |

### Ramp Dimensions
| Element | Dimension |
|---------|-----------|
| Max slope | 6.67% (1:15) parking |
| Max slope | 15% (1:6.67) express |
| Min width | 12' one-way |
| Min width | 22' two-way |
| Transition | 8' at 1/2 slope change |
| Turning radius | 25' min (inside) |

### Clearance Heights
| Element | Min Height |
|---------|------------|
| Standard parking | 7'-2" clear |
| Van accessible | 8'-2" clear |
| At structure | 7'-6" (including utilities) |
| Entry/signage | 8'-0" |
| Below sprinkler | 7'-0" clear |

### Structural Bays
| Bay Type | Size | Notes |
|----------|------|-------|
| Long span | 60' × 30' | Most efficient |
| Short span | 30' × 30' | Column in aisle |
| Optimized | 54' × 27' | Balance of both |

---

## Accessible Parking

### Quantity Required
| Total Spaces | Accessible Required |
|--------------|---------------------|
| 1-25 | 1 |
| 26-50 | 2 |
| 51-75 | 3 |
| 76-100 | 4 |
| 101-150 | 5 |
| 151-200 | 6 |
| 201-300 | 7 |
| 301-400 | 8 |
| 401-500 | 9 |
| 501-1000 | 2% |
| Over 1000 | 20 + 1 per 100 over 1000 |

### Van Accessible Requirement
- 1 per 6 accessible spaces (or fraction)
- 8' wide access aisle (not 5')
- 8'-2" vertical clearance

### Design Requirements
| Element | Requirement |
|---------|-------------|
| Access aisle width | 5' (8' van) |
| Max slope | 2% any direction |
| Surface | Firm, stable, slip-resistant |
| Signage | ISA symbol, 60" min height |
| Location | Shortest accessible route |

---

## Drive Aisles and Circulation

### Driveway Dimensions
| Type | Width | Throat Length |
|------|-------|---------------|
| One-way entry | 12'-14' | 20' min |
| Two-way | 22'-26' | 30' min |
| Service/loading | 12' one-way | 50' min |

### Intersection Sight Distance
| Speed | Min Distance |
|-------|--------------|
| 15 mph | 100' |
| 20 mph | 125' |
| 25 mph | 155' |
| 30 mph | 200' |
| 35 mph | 250' |

### Traffic Flow
| Lot Size | Recommended |
|----------|-------------|
| < 50 spaces | Two-way aisle OK |
| 50-200 spaces | One-way preferred |
| > 200 spaces | Separated entry/exit |

---

## Parking Lot Grading

### Slope Requirements
| Surface | Min | Max |
|---------|-----|-----|
| Parking stalls | 1% | 5% |
| Drive aisles | 1% | 5% |
| Pedestrian areas | 2% cross | 5% running |
| Accessible stalls | - | 2% |
| Ramps (structure) | - | 6.67% |

### Drainage
| Element | Guideline |
|---------|-----------|
| Catch basin spacing | 300' max on grade |
| Gutter flow width | 8' max at design storm |
| Inlet capacity | Per local standards |
| Detention | Per stormwater requirements |

---

## Striping and Pavement Markings

### Stripe Dimensions
| Marking | Width | Notes |
|---------|-------|-------|
| Stall line | 4" | White or yellow |
| Aisle line | 4" | White or yellow |
| Stop line | 12"-24" | White |
| Crosswalk | 6" wide, 10' long | White |
| Handicap symbol | 36" × 36" | Blue/white |
| Arrows | Per MUTCD | White |
| No parking | N/A | Red curb or signs |

### Paint Types
| Type | Durability | Cost |
|------|------------|------|
| Water-based | 6-12 months | $ |
| Solvent-based | 12-18 months | $$ |
| Thermoplastic | 3-5 years | $$$ |
| Epoxy | 3-5 years | $$$ |

---

## Lighting

### Light Levels (Foot-candles)
| Area | Min | Max |
|------|-----|-----|
| Parking (open) | 1.0 | 5.0 |
| Parking (covered) | 5.0 | 10.0 |
| Drive aisle | 1.0 | 2.0 |
| Entry/exit | 5.0 | 10.0 |
| Pedestrian areas | 2.0 | 5.0 |

### Pole Spacing
| Pole Height | Approximate Spacing |
|-------------|---------------------|
| 20' | 60'-80' |
| 25' | 80'-100' |
| 30' | 100'-120' |

### Light Pollution Control
- Full cutoff fixtures
- Max 0.1 FC at property line
- Shielding as required

---

## Parking Calculations

### Ratios by Use (Typical)
| Use | Ratio |
|-----|-------|
| Office | 1 per 250-400 SF |
| Retail | 1 per 150-250 SF |
| Restaurant | 1 per 50-100 SF |
| Fast food | 1 per 30-50 SF |
| Medical office | 1 per 150-200 SF |
| Hospital | 1 per 2-3 beds |
| Church | 1 per 3-5 seats |
| Theater | 1 per 3-4 seats |
| Multi-family | 1-2 per unit |
| Hotel | 1 per room + 1 per 4 employees |
| Industrial | 1 per 500-1000 SF |

### Efficiency Calculations
```
Gross lot area × Efficiency factor = Net parking area
Net parking area ÷ SF per space = Total spaces

Typical efficiency factors:
- Surface lot: 300-350 SF/space
- Structured (90°): 350-400 SF/space
```

---

## EV Charging

### Requirements (Growing)
| Jurisdiction | Requirement |
|--------------|-------------|
| California | 10% EV-ready (new construction) |
| Florida | Varies by city |
| Federal | May apply to federally-funded |

### Charging Levels
| Level | Voltage | Range/Hour | Use |
|-------|---------|------------|-----|
| Level 1 | 120V | 3-5 miles | Home overnight |
| Level 2 | 240V | 10-30 miles | Workplace, commercial |
| DC Fast | 480V | 100+ miles | Highway, quick stop |

### Infrastructure Requirements
| Level | Electrical | Space |
|-------|------------|-------|
| Level 1 | Standard outlet | Any |
| Level 2 | 40A circuit | End of row preferred |
| DC Fast | 480V 3-phase | Separate area |

---

## Pedestrian Safety

### Crosswalks
- At all pedestrian routes across drive aisles
- Striped minimum 6' wide
- Speed tables/raised crossings for high traffic

### Sidewalks
- Continuous along building
- Connect to parking aisles
- 5' min width (6' preferred)
- ADA compliant routes

### Traffic Calming
| Device | Effect |
|--------|--------|
| Speed bumps | 15 mph |
| Speed tables | 25 mph |
| Raised crosswalk | 15-20 mph |
| Tight turns | Slow entry |

---

## Parking Structure Specifics

### Structural Systems
| System | Span | Cost |
|--------|------|------|
| Cast-in-place | 60' | $$$$ |
| Precast single-tee | 60' | $$$ |
| Precast double-tee | 60' | $$$ |
| Steel frame | 60'+ | $$$ |
| Post-tensioned | 60'+ | $$$$ |

### Facade Considerations
- Required openings for ventilation
- 50% open typical requirement
- Architectural screen options
- Safety cables at openings

### Mechanical Systems
| System | When Required |
|--------|---------------|
| Ventilation | If < 50% open |
| CO detection | If enclosed |
| Fire sprinklers | If enclosed or > 48" closure |
| Drainage | All levels |

---

## Signage

### Required Signs
| Sign | Location |
|------|----------|
| Entry/exit | At driveways |
| Height clearance | At entry |
| Speed limit | Throughout |
| Stop | At exits, intersections |
| One-way arrows | Aisles |
| Accessible parking | At spaces |
| Floor/zone ID | Structures |
| Emergency contact | Visible locations |

### Wayfinding (Structures)
- Floor numbers/colors
- Entry/exit directions
- Elevator/stair locations
- Emergency egress routes
