Cracks Around Window Frame: Updated

| Crack Type | Morphology | Typical Width | Severity Index | | :--- | :--- | :--- | :--- | | | Hairline vertical/horizontal at frame edge; no displacement | < 0.5 mm | Low | | Type II (Seasonal) | Recurring straight crack; opens in winter, closes in summer | 0.5 - 1.5 mm | Moderate | | Type III (Structural) | Diagonal from corners; step-cracking in masonry; visible displacement | > 1.5 mm or tapered | High | | Type IV (Moisture) | Accompanying paint bubbling, efflorescence, or soft drywall | Variable | Critical |

A common non-structural cause is the "drywall butt joint" positioned directly over the window edge. If drywall sheets are hung without proper staggering, the natural seam may align with the frame. Without adequate tape and compound reinforcement, this seam cracks inevitably. Additionally, insufficient shimming or over-tightening of fasteners can pre-stress the frame, inducing immediate cracking after initial occupancy. cracks around window frame

The primary causes of cracking can be categorized into four domains: | Crack Type | Morphology | Typical Width