Condensation forms inside tents due to a combination of factors that include a humid and wet environment, temperature fluctuations, and the release of moisture within the tent, often from the occupants themselves. While it is challenging to control the environment, choosing the right campsite can play a critical role. Selecting a location away from vapor-emitting features like rivers, oceans, and bodies of water can help reduce the amount of water vapor in the surrounding air, ultimately minimizing condensation.
Temperature changes also contribute to condensation, as cooler temperatures have a lower capacity to hold water vapor. Additionally, during the night, adult humans can exhale approximately 1-2 pints of water, creating warm and moisture-laden air that needs to find an escape. Unfortunately, much of this air becomes trapped inside the tent, leading to condensation formation and the potential for dripping onto the occupants. Furthermore, rainstorms often saturate the air with water vapor, prompting tents to be fully sealed to keep occupants and gear dry. However, this prevents air circulation within the shelter, causing trapped humid air to interact with the slightly cooler fabric, resulting in condensation.
Maximizing ventilation is the best way to minimize condensation. If you observe moisture inside the tent, you can use a towel or other absorbent material to wipe it away. It's important to note that a common myth suggesting that touching the tent's walls or roof during a rainstorm will make liquid pass through the fabric is completely false. In fact, keeping the inside of the fabric dry enables vapor to escape more efficiently.