Humidity, Temperature, and Your Guitar

Being on the cusp of another seasonal change here in Brisbane, we thought it would be timely to share some information about the proper care and environment for your guitar. This is a 5 minute read for any of our customers who are keen to give their guitar the best possible conditions to thrive, would like to avoid costly repairs, or are just curious about humidity and guitars in general.

To protect your solid wood guitar, it is crucial to know how temperature and humidity can affect it. Living in Australia, we experience fluctuating humidity levels all year round. It helps to have a good grasp on how to regulate the conditions that your guitar lives in to ensure its safety. We see many cases of humidity related issues in the repair department at Guitar Brothers, so it's our hope the following advice might assist you to properly care for your instrument with consideration of these variables.

What is humidity and how will it affect my guitar?

Humidity refers to the amount of moisture or water vapor present in the air, with higher levels indicating greater moisture content and lower levels indicating less. Most experts would say that maintaining a humidity level of 45-55% in your guitar is essential to prevent cracking, swelling and a loss of tone and volume. Excessive humidity can also lead to discoloration of the finish, along with mould growth inside the guitar, which is never a good thing (unless you’re using your old guitar to sprout some delicious oyster mushrooms!)

The first 3-5 years are crucial for an acoustic guitar's humidity control. If the guitar is properly stabilized during that time, it is less likely to have issues. Vintage instruments are typically less affected by humidity changes than newer ones for this reason.

What kinds of guitars need humidity control?

All types of guitars, including electric solid bodies, require humidification. Solid wood acoustics, however, require the most attention due to their sophisticated construction. Newer guitars need more moisture as they are made from kiln-dried wood, unlike vintage guitars made from air-dried wood. Kiln-dried wood is more susceptible to warping and cracking, and therefore requires additional moisture to prevent damage. On the other hand, vintage guitars made from air-dried wood were more stable and less prone to cracking due to the aging process. These guitars still require humidity to maintain optimal sound quality but retain moisture better than modern guitars. It’s important to note that it’s often the more expensive guitars that are the most susceptible to humidity and temperature changes. Generally they are more finely and precisely built from extremely thin solid timber. It seems counter intuitive, but cheaper guitars are more heavily built, or even made of plywoods (being more rigid and robust, but sacrificing tone in the process). 

Can temperature affect my guitar?

Yes, exposure to high temperatures can cause significant damage to a guitar. For example, leaving a guitar in your car, particularly on a hot day, can result in the failure of the glue joints. This could cause the guitar to fall apart. Here at Guitar Brothers we have seen many cases of heat-damaged guitars, and the cost of repairing them can often be very high. Therefore, it is crucial to be careful and take necessary precautions to avoid exposing your guitar to excessive heat. 

Cold temperatures also can harm guitars and cause finish checking, which creates small cracks in the finish that cannot be polished out and require refinishing. 

Avoid rapid changes in humidity and temperature

To protect your guitar, avoid rapid changes in humidity, as this can also cause severe damage. For instance, moving a guitar from 85% humidity to 35% abruptly can be harmful. If you find yourself in this position, it’s recommended that you place your guitar in its case and gradually expose it to a drier but humidified environment over a few weeks. The guitar case serves as an excellent tool for insulating the guitar from extreme conditions and rapid changes.

Here’s a few safety measures you can take to protect your guitar from costly repairs.

A great way to control humidity is to use a two-way humidification system for guitars. Think of it as an inexpensive insurance policy to protect you from very expensive repairs. Modern guitar humidifiers utilize a gel that has the capability to both emit and absorb humidity. This technology, which was initially created for cigar humidors, has now been adapted for guitars. Two notable examples of this are the Humidipak, produced by D’addario and the Two Way Humidity Control Pack by Boveda. Both of which we have here at Guitar Brothers (links below).

Store your guitar in its case to insulate it from extreme conditions and rapid changes. Especially when traveling with your guitar to a different climate, it’s recommended that you keep your guitar in its case while it adapts to its new environment, this can take up to a few weeks. 

Use a hygrometer. A handy way to keep track of the humidity of your guitar is placing a hygrometer in its case, or in the room where the guitar is stored. This will tell you the relative humidity in the guitar’s little home, so you know when to take action if needed. 

Keep your guitar out of direct sunlight and never leave it in a hot car. Instead, keep your guitar in a consistent environment. Air conditioned rooms are great for guitars where the air conditioner is set to control both the temperature and humidity. 

As always, we are happy to discuss the “care and feeding” of your instrument, along with assistance and advice for moving or shipping guitars. Please do not hesitate to contact us if you have any questions or suggestions, and happy playing!

- The team at Guitar Brothers!