# Performance Specification Gap in Division 32 Exterior Improvements submittals

> Source: https://deviationcheck.com/divisions/32-exterior-improvements/performance-specification-gap/

A measurable performance property in the submittal (rating, capacity, tolerance, efficiency) does not meet what the spec requires.

## What to look for in Division 32 Exterior Improvements

Key performance parameters in exterior improvement submittals:
- **HMA binder grade** (PG XX-XX) - must match climate zone and traffic loading; submitting PG 58-28 where PG 64-22 is specified is a blocker in cold climates
- **Asphalt compaction target** - % of maximum theoretical density (Marshall method: 96%, Superpave: 92-96% of Gmm); look for design vs field target
- **Asphalt mix design parameters** - % passing each sieve, voids in mineral aggregate (VMA), air voids (target 3-5% in field), voids filled with asphalt (VFA)
- **Concrete paving compressive strength** (f'c) - typically 4000 psi at 28 days for parking lots, 4500 psi for driveways, 5000 psi for heavy truck; verify submitted mix meets spec
- **Concrete air content** - 5-7% for freeze-thaw exposure (ACI 301 Table 4.4.1); lower air content in freeze climates is a blocker
- **Concrete fiber type and dosage** - polypropylene, steel, or synthetic macro fiber at specified lb/cy; fiber type affects crack control differently
- **Aggregate base gradation** and compaction (% Proctor) - must match geotechnical recommendation
- **Irrigation precipitation rate** (in/hr) per zone - must not exceed soil infiltration rate; mixed head types in same zone cause uneven coverage
- **Irrigation uniformity coefficient (DU, distribution uniformity)** - minimum 0.70 for turf, 0.75 for potable water districts
- **Plant caliper size** - must meet ANSI Z60.1 nursery stock grades; caliper measured 6" above grade for trees up to 4" caliper
- **Plant height and spread** at time of delivery per ANSI Z60.1 grade requirements
- **B&B vs container** specification - not interchangeable; B&B trees have established root balls, container stock has different acclimation requirements
- **Athletic surface Gmax** impact attenuation - maximum 200g per ASTM F355; exceeding this is a safety blocker
- **Synthetic turf pile height and fiber weight** (oz/sq yd) - affects playability, durability, and heat retention

## Severity

Default grade: Blocker. Always a Blocker when the gap touches life-safety or structural performance.