Water inside the substrate or casing is a crop resource. Humidity describes water vapour in the air. Surface wetness is liquid water on the mushroom or structure. These conditions interact but cannot be substituted for one another. Increasing humidification may not restore water to a dry casing layer, and adding water to a bed may leave unwanted wetness on caps.
Condensation occurs when a surface is cool enough for moisture in surrounding air to condense. Review product or surface temperature, air conditions and recent cooling or door-opening events when droplets appear. Air movement can help evaporation but can also dry exposed crop zones. The useful question is where moisture goes after an adjustment, not whether the room feels damp.