Possible causes
- Damaged or badly fitted flashing kit
- Blocked gutter channels above the window
- Worn window seals
- Condensation running off the glass (not a roof leak at all)
Warning signs
- Water on the window lining or reveal
- Stains below the window after rain
- Drips only in cold weather — often condensation
Typical solutions
- Clearing debris from above the window
- Refitting or renewing the flashing kit
- Advice on ventilation where condensation is the cause