Humidity basics
Understand the signs
Humidity basics.
Make sense of basement humidity readings, spot patterns and find the source before changing equipment.
Field notes and guides
Start with a question. Leave with a plan.
Explore one topic at a time, then follow the related reading inside each guide.
Humidity basics
Why Basement Relative Humidity Changes With Temperature
A change in your basement’s relative humidity does not, by itself, tell you how much water was added or removed. The percentage depends on temperature as well as water vapor. Compare the temperature, location, and conditions beside each reading before deciding that a higher number means a new moisture source. NOAA explains the temperature relationship. […]
Humidity basics
Condensation or a Leak: What to Record First
A wet basement wall, floor, or pipe can suggest several possible moisture sources. A photo or a single humidity reading usually leaves important context missing. Start by recording where the water is, when you noticed it, and what was happening around that time. Describe what you observed before assigning a cause. This guide helps you […]
Humidity basics
Outdoor vs. Indoor Humidity: How to Compare Readings
You cannot decide whether outdoor air is drier than basement air by comparing the relative-humidity percentages alone when their temperatures differ. Keep temperature and, when available, dew point with each reading. A weather app and a room meter also represent different places, so write down their sources before treating them as a matched comparison. Why […]
Humidity basics
Why Your Dehumidifier and Hygrometer Readings Differ
If your dehumidifier and a separate hygrometer show different humidity percentages, first check what each number means. The appliance may be showing the target you selected, a current reading, or another display state. Then record where each sensor is and when you checked it. A disagreement alone does not establish that either device is faulty. […]
Humidity basics
How to Keep a Useful Basement Humidity Log
A useful humidity log records the room, temperature and conditions alongside each reading. Build a simple routine and export your observations as a CSV.
Humidity basics