What impact does relative humidity have on building comfort during warmer months?

Relative humidity plays a significant role in determining indoor comfort, particularly during the warmer months. Higher relative humidity levels can hinder the body’s natural cooling process, which primarily relies on the evaporation of sweat. When humidity is high, the air is already saturated with moisture, making it challenging for sweat to evaporate. This can lead to a feeling of mugginess and discomfort, as the body struggles to maintain its internal temperature.

In this context, when the air feels sticky or oppressive due to elevated humidity levels, it can result in discomfort and potentially heat stress. Individuals may experience symptoms such as lethargy, irritability, or even heat-related illnesses if the humidity levels remain high over prolonged periods. Therefore, the correct understanding is that high relative humidity can lead to discomfort and heighten the risk of heat stress during warmer months, negatively impacting overall thermal comfort within a building.