How to use this result
Bedroom damp is a sleep-environment issue because it changes comfort, window moisture, smell and how often the room needs ventilation. The checker uses dew point logic as a practical clue, not as proof of what every window surface is doing.
The best use is a two-night comparison: enter the room temperature and RH at bedtime, note the glass in the morning, then repeat after one change such as earlier ventilation or removing wet clothes from the room.
If the result points to repeated moisture, the next step is to remove sources and improve ventilation before assuming the whole room needs heating.
Run the tool, choose one change, repeat it for two or three nights, then compare the room notes. A repeated pattern is more useful than one perfect-looking number.
