Quality Control & Testing

Module 5: Quality Control & Testing

5.1 Mock-Up Testing & Performance Validation

Purpose: Verify design integrity before full-scale installation.

Key Components of Mock-Up Testing

• Full-Scale Sample Panel (3m x 3m minimum)

• Includes all materials, joints, and anchoring systems

• Represents worst-case conditions (e.g., corner units)

Testing Protocols

1. Static Performance Tests (ASTM E330)

• Applies 150% of design wind load for 10 seconds

• Measures deflection (max L/175 for glass, L/60 for frames)

2. Dynamic Cycling Test (AAMA 501.4)

• 10,000 pressure cycles (simulating 40-year wind events)

• Checks for fastener fatigue or sealant degradation

3. Operational Testing (if applicable)

• 500 open/close cycles for operable windows

Documentation Requirements

• Signed-off by architect, contractor, and testing lab

• Becomes the benchmark for field installation

5.2 Water Penetration & Air Leakage Tests

Field Water Testing (AAMA 501.2)

• Test Apparatus: Spray rack delivering 5L/m²/min at 137km/h wind speed

• Pass/Fail Criteria:

• No water penetration beyond interior drainage plane

• Maximum 0.3L leakage per 10m² in 15 minutes

Chamber Air Leakage Test (ASTM E283)

• Pressure differentials:

• 1.57 psf (75 Pa) for standard buildings

• 6.24 psf (300 Pa) for high-rises

• Acceptable leakage: ≤0.06 cfm/ft² at design pressure

Common Failure Points

• Corner joints (85% of failures occur here)

• Sealant-to-glass interface

• Weep hole blockages

5.3 Deflection & Structural Integrity Checks

Field Measurement Techniques

1. Laser Tracking (for mullions)

• Tolerances: ±3mm over 10m height

• Measures post-installation creep

2. Dial Gauge Testing (for glass)

• Maximum allowable deflection:

• 1/60 of glass short dimension

• 19mm max for typical 6m span

3. Anchor Load Verification

• Torque testing: ±10% of specified value

• Proof loading: 200% of working load for 60 seconds

Critical Checkpoints

• After first significant wind event (≥50% design load)

• Post-construction settlement (6-month review)

5.4 Common Installation Defects & Prevention

Top 5 Defects by Frequency

1. Sealant Failures (32% of issues)

• Cause: Improper joint preparation (dust, moisture)

• Fix: Mandatory 3-point inspection (clean-primer-apply)

2. Glass Stress Fractures

• Cause: Hard contact with frames (missing setting blocks)

• Prevention: 3mm neoprene spacers every 300mm

3. Misaligned Mullions

• Tolerance Stack-Up: Cumulative error >15mm over 5 stories

• Solution: Install from multiple control points

4. Corrosion Staining

• Source: Dissimilar metal contact (steel shims on aluminum)

• Mitigation: Teflon-coated or stainless steel isolation pads

5. Inadequate Firestopping

• Critical Gap: >25mm at slab edges

• Solution: Intumescent wrap strips + fire-rated foam

QA/QC Process Flow

1. Daily Checklists (per 100m² installed)

2. Weekly Third-Party Audits

3. Final Sign-Off Testing (including IR thermography for thermal bridges)

Key Takeaways

• Mock-ups are legal documents - test the exact production materials

• Water testing should simulate real-world worst conditions (wind-driven rain at 45° angle)

• 90% of defects originate from first 10% of installation - emphasize early QC

• Digital twin models can now predict 95% of failure points before installation