In areas with extreme or year round high humidity, place several silica gel or bamboo charcoal packs in the guitar case and change them every few months. Use a room de-humidifier where you store your guitar. It's also wise to monitor the humidity levels with a digital hygrometer.
Does a guitar case protect from humidity?
Hard cases, on the other hand, provide excellent protection against temperature, humidity, and physical damage. ... By storing your guitar in a hard case and allowing it to change temperatures inside the case, you're controlling the temperature change.
How is humidity reduced?
The most surefire way to reduce indoor humidity is to get a dehumidifier. Dehumidifiers fit right inside your furnace air handler, and removes moisture from the air as it passes through. ... You'll actually have to use your air conditioner a lot less, because it now has help keeping humidity levels low.