| name | site-improvements-division-32 |
| description | Division 32 exterior improvements including paving, landscaping, irrigation, fencing, site lighting, and ADA site compliance for construction projects. |
Site Improvements - Division 32
This skill provides comprehensive guidance for Division 32 exterior improvements on commercial and institutional construction projects. It covers paving operations, landscaping, irrigation, fencing, exterior lighting, retaining walls, playgrounds, and site amenities.
Quick Reference Tables
Asphalt Pavement Sections by Application
| Application | Surface Course | Binder Course | Base Course | Aggregate Base |
|---|
| Parking (Light) | 1.5-2" | - | 2-3" | 4-6" |
| Drives/Access | 1.5-2" | - | 2-3" | 6-8" |
| Heavy Duty (Trucks) | 2" | 2-3" | 3-4" | 8-12" |
Concrete Thickness by Application
| Application | Thickness | Reinforcement | Concrete Strength |
|---|
| Sidewalks | 4" | WWF or fiber (optional) | 3500-4000 psi |
| Light Duty Paving | 4" | WWF 6x6-W1.4xW1.4 | 3500 psi |
| Drives/Aprons | 5-6" | WWF 6x6-W2.9xW2.9 | 4000 psi |
| Heavy Duty | 6-8" | #4 @ 18" o.c. EW | 4000 psi |
| Dumpster Pads | 6" min | #4 bars or WWF | 4000 psi |
ADA Accessible Parking Requirements
| Total Spaces | Accessible Required | Van Accessible |
|---|
| 1-25 | 1 | 1 of 6 accessible |
| 26-50 | 2 | 1 of 6 accessible |
| 51-75 | 3 | 1 of 6 accessible |
| 76-100 | 4 | 1 of 6 accessible |
| 101-150 | 5 | 1 of 6 accessible |
| 151-200 | 6 | 1 of 6 accessible |
Accessible Parking Space Dimensions
| Type | Space Width | Access Aisle | Total Width |
|---|
| Standard | 8' | 5' | 13' |
| Van Accessible | 11' | 5' | 16' |
| Van (Alt Layout) | 8' | 8' | 16' |
ADA Slope Requirements
| Element | Maximum Running Slope | Maximum Cross Slope |
|---|
| Accessible Route | 5% (1:20) | 2% (1:50) |
| Curb Ramp | 8.33% (1:12) | 2% (1:50) |
| Parking Spaces | 2% any direction | 2% any direction |
| Flared Sides | 10% (1:10) | - |
Pavement Marking Materials Comparison
| Material | Life Expectancy | Relative Cost | Best Application |
|---|
| Traffic Paint | 1-2 years | Lowest | Low traffic, budget |
| Thermoplastic | 3-5+ years | Medium-High | High traffic areas |
| Epoxy | 3-5 years | Medium-High | Durability needed |
| Preformed Tape | 5-7+ years | Highest | Critical markings |
Standard Parking Space Dimensions
| Angle | Space Width | Space Length | Aisle Width |
|---|
| 90° | 9' | 18' | 24' (two-way) |
| 60° | 9' | 18' | 18' (one-way) |
| 45° | 9' | 18' | 13' (one-way) |
Fence Post Foundation Depths
| Post Height | Minimum Embedment | Footing Diameter |
|---|
| 4' fence | 24" | 8-10" |
| 6' fence | 30" | 10-12" |
| 8' fence | 36" | 12" |
| 10' fence | 42" | 12-14" |
| Gate posts | +6" over line posts | +2" over line posts |
Site Lighting Levels (IES Recommendations)
| Area | Average Footcandles | Uniformity Ratio |
|---|
| Parking (General) | 0.5-1.0 fc | 4:1 max |
| Parking (High Activity) | 1.0-2.0 fc | 4:1 max |
| Walkways | 0.5-1.0 fc | 4:1 max |
| Building Entries | 5.0 fc | 3:1 max |
| Loading Areas | 5.0-10.0 fc | 3:1 max |
| ATMs/Kiosks | 10.0+ fc | 2:1 max |
Pole Foundation Sizing (Typical)
| Pole Height | Foundation Diameter | Foundation Depth | Anchor Bolt Circle |
|---|
| 12-15' | 18" | 36" | 6-8" |
| 20' | 24" | 42" | 8-10" |
| 25-30' | 30" | 48" | 10-12" |
| 35' | 36" | 54" | 12-14" |
Retaining Wall Types and Height Limits
| Wall Type | Max Non-Engineered Height | Reinforcement |
|---|
| Gravity SRW | 3-4' | None |
| Reinforced SRW | 20'+ | Geogrid |
| Timber Wall | 3-4' | Deadmen |
| Boulder Wall | 3-4' | None |
Playground Safety Surfacing Critical Heights
| Surfacing Type | 6" Depth | 9" Depth | 12" Depth |
|---|
| Engineered Wood Fiber | 7' | 10' | 11' |
| Poured-in-Place Rubber | Per manufacturer | Per manufacturer | Per manufacturer |
| Rubber Tiles | Per thickness rating | Per thickness rating | Per thickness rating |
Asphalt Temperature Requirements
| Course Type | Minimum Air Temp | Minimum Surface Temp |
|---|
| Surface Course | 50°F (rising) | 50°F |
| Base Course | 40°F (rising) | 40°F |
Irrigation System Components
| Component | Purpose | Key Specifications |
|---|
| Backflow Preventer | Protect potable water | PVB, RPZ, or DCVA per code |
| Controller | Zone scheduling | Number of stations, smart features |
| Control Valves | Zone activation | Electric or hydraulic |
| Spray Heads | Small area coverage | 4'-15' radius |
| Rotors | Large area coverage | 15'-50'+ radius |
| Drip | Beds and trees | Low flow, point source |
Detailed Reference Guides
Paving Operations
- Asphalt Paving - HMA types, placement, compaction, joints, testing
- Concrete Paving - Sidewalks, drives, pads, finishing, reinforcement
- Curbs and Gutters - Curb types, forming, slip-form, repairs
Markings and Signage
Accessibility
Landscaping and Irrigation
Site Amenities
Specialty Site Work
Compliance and Coordination
- Code Compliance - ADA, fire access, zoning, permits
- Testing and Inspection - Asphalt, concrete, landscape, lighting
- Coordination and Sequencing - Design, sequence, protection
- Seasonal Constraints - Temperature limits, planting seasons
- Safety Hazards - Paving, landscaping, excavation safety
- Specifications CSI - Division 32 sections, related divisions
Critical Coordination Points
With Early-Phase-Enabling-Trades
- Earthwork and rough grading
- Underground utilities (storm, sanitary, water, gas, electric)
- Subgrade preparation and proof rolling
- Erosion control during construction
- Storm drainage infrastructure
With Electrical Systems
- Site lighting power and circuiting
- Conduit routing for poles
- Panel capacity for site loads
- Photocell and control wiring
With Other Trades
- Fire-protection-systems: Fire lane requirements
- Mechanical-plumbing-systems: Exterior drinking fountains
- Low-voltage-technology: Gate access control, security
- Specialties-division-10: Flagpoles, exterior signage
- Quality-control-closeout: Final inspection and documentation
Site Work Sequencing Overview
Phase 1 - Early/Rough
- Earthwork and mass grading
- Underground utilities
- Storm drainage installation
- Subgrade preparation
Phase 2 - Base Work
- Aggregate base installation
- Curbs and gutters
- Concrete paving (non-traffic areas)
- Retaining walls
- Fence post foundations
- Light pole foundations
Phase 3 - Surface Work
- Asphalt paving (base course during construction)
- Concrete drives and aprons
- Asphalt surface course (after heavy traffic)
Phase 4 - Finishes
- Fine grading for landscaping
- Irrigation installation
- Landscaping and planting
- Fencing installation
- Site lighting
- Site furnishings
Phase 5 - Final
- Pavement markings (30-day asphalt cure)
- Signage installation
- Final adjustments and testing
- Punchlist completion
Common Issues and Solutions
Asphalt Problems
| Issue | Cause | Solution |
|---|
| Segregation | Poor handling | Proper transfer, minimize handling |
| Raveling | Insufficient compaction | Proper roller sequence, temperature |
| Bleeding | Too much asphalt | Proper mix design |
| Cracking | Base failure, age | Proper base prep, joint sealing |
Concrete Problems
| Issue | Cause | Solution |
|---|
| Cracking | Insufficient joints | Proper joint spacing (2x thickness) |
| Scaling | Freeze-thaw | Air entrainment, proper curing |
| Discoloration | Curing issues | Consistent curing methods |
| Spalling | Steel corrosion | Adequate cover, proper placement |
Landscape Problems
| Issue | Cause | Solution |
|---|
| Plant mortality | Poor installation | Proper planting depth, watering |
| Poor germination | Wrong timing | Seasonal seeding windows |
| Irrigation dry spots | Design/installation | Head adjustment, coverage check |
| Erosion | Slope/timing | Stabilization, erosion control |
Key Inspection Points
Pre-Paving Checklist
Pre-Landscaping Checklist
Final Site Checklist
