Musical instruments are sensitive to environmental conditions and can easily be damaged if conditions aren’t controlled. The tone woods used in musical instruments (particularly acoustic guitars, violins, cellos, and percussion instruments) are sensitive to temperature and humidity. Low humidity can cause wood to dry out, warp, or crack. High humidity can potentially cause corrosion of acoustic guitar strings, as well as electronics in electric instruments and microphones. Rapid changes in temperature and humidity are, many believe, the most damaging to musical instruments.
Proper temperature and humidity conditions for a musical instrument and guitar storage will vary by instrument type and manufacturer. Typically speaking, 40-55% relative humidity and a temperature range of 68-72°F (comfortable indoor room levels) is safe. That said, ALWAYS check with the manufacturer for precise levels. Also, maintain a stable environment and avoid rapid changes in temperature and guitar humidity. If the music room is in the basement, do not set instruments directly on the concrete as this can leach away moisture, as well as conduct cold. To help protect items from flood damage, store everything at least a foot or two off the ground. If storing on a lower floor of your home, avoid keeping items directly below potential sources of leaks. Examples include a bathroom, washer/dryer, or dishwasher. For best results, continually monitor for humidity, temperate, and leaks, and use a guitar humidifier if recommended by the manufacturer.