# Parking Structures

## Structure Types

### By Configuration
| Type | Description | Efficiency |
|------|-------------|------------|
| Self-park | User parks, retrieves | 300-350 SF/space |
| Valet | Attendant parks | 250-300 SF/space |
| Automated | Mechanical system | 150-200 SF/space |
| Robotic | AGV retrieval | 175-225 SF/space |

### By Construction
| Type | Description |
|------|-------------|
| Cast-in-place | Poured on site |
| Precast | Factory-made panels |
| Post-tensioned | Tensioned cables |
| Steel frame | Steel with precast |
| Hybrid | Mixed systems |

### By Grade Relationship
| Type | Description |
|------|-------------|
| Above grade | Open deck or enclosed |
| Below grade | Underground |
| Partially below | Split-level |
| Podium | Supporting building above |

---

## Dimensional Standards

### Stall Dimensions
| Type | Width | Length |
|------|-------|--------|
| Standard | 8'-6" to 9'-0" | 18'-0" |
| Compact | 7'-6" to 8'-0" | 15'-0" to 16'-0" |
| Accessible | 8'-0" + 5' aisle | 18'-0" |
| Van accessible | 8'-0" + 8' aisle | 18'-0" |
| Motorcycle | 4'-0" | 8'-0" |

### Aisle Widths
| Parking Angle | One-Way | Two-Way |
|---------------|---------|---------|
| 90° | 24'-0" | 24'-0" |
| 60° | 18'-0" | 20'-0" |
| 45° | 13'-0" | 20'-0" |
| Parallel | 12'-0" | 20'-0" |

### Module Dimensions (90° Parking)
| Element | Dimension |
|---------|-----------|
| Single-loaded bay | 27'-0" to 28'-0" |
| Double-loaded bay | 62'-0" to 64'-0" |
| Stall depth | 18'-0" |
| Aisle | 24'-0" |
| Column spacing | 27'-30' x 60'-62' |

### Clearances
| Element | Minimum |
|---------|---------|
| Floor-to-ceiling | 7'-0" |
| Clear height at structure | 7'-2" |
| Clear at signs/pipes | 7'-0" |
| Van accessible route | 8'-2" |
| Truck dock | 14'-0" |

---

## Ramp Design

### Ramp Types
| Type | Description |
|------|-------------|
| Straight | Simple, long |
| Curved | Continuous helix |
| Express | No parking on ramp |
| Speed ramp | Steep, short |
| Cross-aisle | Connects parking bays |
| Double helix | Separate up/down |

### Ramp Slopes
| Ramp Type | Maximum Slope |
|-----------|---------------|
| Standard | 5-6% (6.67% absolute max) |
| Speed ramp | 12-15% |
| Pedestrian ramp | 8.33% (ADA) |
| Transition (top/bottom) | 4% for 16' |
| Cross slope | 2% maximum |

### Ramp Dimensions
| Element | Minimum |
|---------|---------|
| Width (one-way) | 12'-0" |
| Width (two-way) | 24'-0" |
| Turning radius (inside) | 28'-0" |
| Transition length | 16'-0" |

### Helix Design
| Parameter | Standard |
|-----------|----------|
| Rise per turn | 10'-12' |
| Inside radius | 28'-30' |
| Outside radius | 56'-60' |
| Speed | 10-15 MPH design |

---

## Structural Systems

### Framing Options
| System | Span | Advantages |
|--------|------|------------|
| Cast-in-place | 60' typical | Monolithic, flexible |
| Double-tee | 60'-65' | Fast, economical |
| Single-tee | 50'-60' | Wider spans |
| Hollow core | 30'-40' | Short spans |
| Steel beam | Varies | Light, flexible |

### Floor Systems
| System | Thickness |
|--------|-----------|
| Post-tensioned slab | 6"-7" |
| Double-tee | 24"-32" |
| Cast-in-place pan | 8"-10" total |
| Composite steel | 5"-6" deck |

### Foundation Types
| Condition | System |
|-----------|--------|
| Good bearing | Spread footings |
| Poor soil | Deep foundations |
| High water table | Waterproof mat |
| Adjacent buildings | Underpinning |

---

## Drainage and Waterproofing

### Floor Drainage
| System | Application |
|--------|-------------|
| Trench drains | Ramp transitions |
| Area drains | Low points |
| Sloped floors | 1-2% to drains |
| Deck coatings | Exposed structures |

### Waterproofing
| Location | System |
|----------|--------|
| Below grade walls | Membrane |
| Below grade slab | Under-slab membrane |
| Elevated decks | Traffic-bearing membrane |
| Expansion joints | Sealed systems |
| Precast joints | Sealant, membrane |

### Deck Coatings
| Type | Application |
|------|-------------|
| Penetrating sealer | Minimal protection |
| Traffic-bearing membrane | Elevated decks |
| Polyurethane | Medium duty |
| Epoxy | Heavy duty |
| Urethane chip | Decorative, protected |

---

## MEP Systems

### Ventilation
| Type | Requirement |
|------|-------------|
| Open structure | Natural (50%+ open) |
| Enclosed | Mechanical, 6-10 ACH |
| Occupied | 0.75 CFM/SF |
| Carbon monoxide | CO monitoring required |

### Electrical
| System | Standard |
|--------|----------|
| Lighting power | 0.2-0.5 W/SF |
| EV charging | 5-10% spaces |
| Emergency power | Exit lighting, ventilation |
| Fire alarm | Per code |
| CCTV | Cameras throughout |

### Lighting Levels
| Area | Foot-Candles |
|------|--------------|
| Parking areas | 5-10 FC |
| Ramps | 10 FC |
| Stairwells | 10 FC |
| Entry/exit | 50 FC |
| Elevator lobbies | 20 FC |

### Fire Protection
| System | Requirement |
|--------|-------------|
| Sprinklers | Enclosed structures |
| Standpipes | All (dry OK if unheated) |
| Extinguishers | Per code |
| Fire separation | 2-hour to occupied |

---

## Circulation and Wayfinding

### Traffic Flow
| Pattern | Description |
|---------|-------------|
| One-way | Counter-clockwise preferred |
| Two-way | Requires wider aisles |
| Express lanes | Skip levels |
| Separate in/out | Efficient at peak |

### Signage
| Type | Purpose |
|------|---------|
| Directional | Route guidance |
| Level identification | Floor designation |
| Stall numbering | Location reference |
| Clearance | Height warnings |
| ADA | Accessible route |

### Parking Guidance
| System | Function |
|--------|----------|
| Space indicators | Red/green lights per space |
| Level counts | Available spaces per floor |
| Digital signs | Direct to open areas |
| App integration | Reserve, locate vehicle |

---

## Accessibility

### Accessible Spaces Required
| Total Spaces | Accessible | Van |
|--------------|------------|-----|
| 1-25 | 1 | 1 |
| 26-50 | 2 | 1 |
| 51-75 | 3 | 1 |
| 76-100 | 4 | 1 |
| 101-150 | 5 | 1 |
| 151-200 | 6 | 1 |
| 201-300 | 7 | 2 |
| 301-400 | 8 | 2 |
| 401-500 | 9 | 2 |
| 501-1000 | 2% | 1/6 |
| 1001+ | 20 + 1/100 | 1/6 |

### Accessible Features
| Element | Requirement |
|---------|-------------|
| Location | Shortest route to entrance |
| Slope | 2% maximum |
| Signage | ISA symbol |
| Van clearance | 98" route |
| Access aisle | 5' or 8' (van) |

### Accessible Route
| Element | Requirement |
|---------|-------------|
| Width | 36" minimum |
| Elevator | To all levels |
| Ramps | 1:12 maximum |
| Doors | 32" clear |
| Signage | Tactile at elevator |

---

## Security

### Passive Security
| Feature | Purpose |
|---------|---------|
| Open design | Natural surveillance |
| Lighting | Consistent levels |
| Sight lines | Clear visibility |
| Stair visibility | Glass, open |
| Elevator glass | See inside |

### Active Security
| System | Coverage |
|--------|----------|
| CCTV | All areas |
| Access control | Gates, doors |
| Intercoms | Emergency stations |
| Patrols | Periodic |
| License plate readers | Entry/exit |

### Emergency Features
| Feature | Requirement |
|---------|-------------|
| Emergency phones | Every level |
| Blue lights | Emergency stations |
| Exit signage | Illuminated |
| Stairwell access | Re-entry capability |
| ADA phones | Accessible height |

---

## Revenue Control

### Access Systems
| Type | Application |
|------|-------------|
| Gate arms | Entry/exit control |
| Ticket dispensers | Transient parking |
| Card readers | Monthly parkers |
| License plate | Ticketless entry |
| Pay stations | Exit payment |

### Payment Options
| Method | Description |
|--------|-------------|
| Pay on foot | Station before vehicle |
| Pay in lane | At exit |
| Monthly pass | Pre-paid access |
| Validation | Retailer stamps |
| Mobile pay | App-based |

---

## Special Considerations

### EV Charging
| Level | Voltage | Time to Full |
|-------|---------|--------------|
| Level 1 | 120V | 8-12 hours |
| Level 2 | 240V | 4-6 hours |
| DC Fast | 480V | 30-60 minutes |

| Requirement | Standard |
|-------------|----------|
| Code minimum | Varies by jurisdiction |
| LEED | 2% + 3% ready |
| Future-proof | Conduit to 20% |

### Bicycle Parking
| Type | Space |
|------|-------|
| Rack (outdoor) | 6' x 2' |
| Locker | 6' x 2.5' x 4' |
| Cage (secure) | 6' x 2' |
| Stacked | 3' x 6' x 4' |

### Truck/Loading
| Vehicle | Clearance | Stall |
|---------|-----------|-------|
| Passenger car | 7'-0" | 9' x 18' |
| SUV/Truck | 7'-2" | 9' x 20' |
| Van | 8'-2" | 9' x 22' |
| Box truck | 12'-0" | 12' x 35' |
| Semi | 14'-0" | 12' x 65' |

---

## Cost Factors

### Construction Costs (2024)
| Type | Cost/Space |
|------|------------|
| Surface lot | $3,000-5,000 |
| Above-grade structure | $20,000-35,000 |
| Below-grade structure | $40,000-60,000 |
| Automated | $30,000-50,000 |

### Operating Costs
| Item | Annual/Space |
|------|--------------|
| Utilities | $200-400 |
| Maintenance | $200-400 |
| Security | $100-300 |
| Insurance | $50-150 |
| Management | $100-200 |
| **Total** | **$650-1,450** |

### Revenue Factors
| Factor | Impact |
|--------|--------|
| Location | Primary driver |
| Demand | Occupancy rate |
| Pricing | Market rate |
| Mix | Monthly vs transient |
| Validation | Lost revenue |
