Common Ventilation Defects
- Deteriorated, sagging sheathing
- Mildew
- Rust on nail heads at sheathing
- Ventilation fan inoperative or doesn't come on when manually operated
- FRT plywood (some)
- No provision for ventilation (usually older homes)
- Soffit vents blocked or undersized
- Gable vents blocked or undersized
- Ridge vents blocked or not fully cut through the sheathing
- Inadequate or insufficient ventilation configuration
- Vent fans (bath, dryer, kitchen) do not discharge to exterior

