# Performance Specification Gap in Division 04 Masonry submittals

> Source: https://deviationcheck.com/divisions/04-masonry/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 04 Masonry

Key performance parameters in masonry submittals:
- **CMU compressive strength** (f'm prism strength, unit strength per ASTM C90: typically 1900-3000 psi for load-bearing)
- **CMU weight class** (normal weight ~135 pcf, medium weight ~105-125 pcf, lightweight ~85-105 pcf)
- **CMU moisture content** (Type I moisture-controlled vs Type II non-moisture-controlled)
- **Brick compressive strength** (psi per ASTM C62, C216, or C652)
- **Brick absorption rate** (% per ASTM C67, affects bond and freeze-thaw durability)
- **Brick grade** (SW Severe Weathering, MW Moderate Weathering per ASTM C62/C216)
- **Mortar type** (M, S, N, O per ASTM C270 - property vs proportion specification)
- **Grout strength** (f'g psi at 28 days per ASTM C476)
- **Reinforcing steel grade** (Grade 60 per ASTM A615/A706)
- **Stone flexural strength** (modulus of rupture per ASTM C99/C880)
- **Stone absorption rate** (% per ASTM C97)
- **Fire rating** of masonry assembly (hours per UL/WHI listing or calculated per TMS 216)
- **STC rating** of masonry assembly
- **Thermal resistance** (R-value of insulated masonry assembly)

## Severity

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