1. Stop at the safety boundary
Do not assume all skylight water is failed exterior flashing or all of it is condensation.
2. Capture the baseline
Take one context photo, one close view and a short note describing location, date, weather, recent water use, equipment state and occupancy.
3. Track the trigger
Snow cover followed by sun, rising outdoor temperature or indoor humidity.
4. Compare, do not assume
Supports this pathway
- The drip begins as roof snow melts
- Moisture appears at one frame corner
- Attic frost or ice is visible around the opening
Weakens this pathway
- The same leak occurs in warm rain with no snow
- Indoor humidity is low and no frost is present
- The glazing unit itself is fogged between panes only
5. Repeat only safe checks
- Record indoor humidity and outdoor temperature
- Photograph the exact first wet edge
- Compare a thaw event with a later rain event
6. Decide the next step
If the pattern is active, expanding, safety-related or requires opening inaccessible construction, stop self-help testing and prepare an evidence-based handoff. Use a roofer for exterior opening and a building professional when air leakage or condensation around the shaft is suspected.
7. Verify the outcome
After any action, repeat the same observation under a comparable trigger. A dry surface immediately after work is not sufficient proof when the original symptom was intermittent.
