What is the recommended residential indoor relative humidity?

The recommended residential indoor relative humidity is typically around 50%. This level of humidity is considered ideal for maintaining comfort and promoting health within a living environment. When humidity is maintained at this level, it helps prevent the growth of mold and mildew, reduces the risk of respiratory problems, and minimizes issues associated with dry air, such as dry skin and static electricity.

Maintaining a relative humidity level around 50% also supports efficient operation of heating and cooling systems, as proper humidity levels allow for more comfortable temperatures without overworking HVAC equipment. While some variations in recommendations exist, 50% humidity strikes a balance between comfort, health, and energy efficiency for most residential situations.