Acoustic guitars and ukuleles are made of wood, and wood is sensitive to changes in climate. Shifts in temperature or relative humidity can affect your instrument in multiple ways, some of which can lead to costly repairs if you’re not careful. Solid woods in particular are especially prone to the effects of climate fluctuation. For example, extended exposure to low relative humidity (below 40% RH) can dry out the wood, causing it to shrink and run the risk of cracking. Similarly, excessive humidity (above 60% RH) can cause the wood to absorb moisture and swell, potentially causing other problems. Without adequate humidity control, acoustic instruments can crack or swell and their necks can warp, causing problems with fretting, intonation and playability.

So how do you prevent this kind of damage? Easy: by keeping your guitars and ukulele properly humidified (ideally between 40-60% RH). The easiest way to do this is by storing your instruments in a case with a case  two-way Humidifier inside. A two-way Humidifier will slowly absorb or release moisture inside your case, maintaining humidity to help ensure your instrument doesn’t suffer damage. Using a digital hygrometer can help you monitor humidity levels around your instrument. 

If you insist on having your guitars out of the case hanging on the wall or on a stand then you should consider purchasing a digital hygrometer to measure/gauge the humidity in the room/environment. If the humidity in the room/environment is above 60% then we recommend purchasing an Ausclimate Dehumidifier to bring the humidity down to the required 45-55%. Similarly, if the Humidity in the room/environment is below 40% we recommend purchasing a Humidifier to bring the humidity up to the required 45-55%. Humidity does fluctuate substantially depending on the time of the year, your location and each room/environment of your location. 

Symptoms of a dry acoustic instrument:

• Low action. Strings are very close to the fretboard.
• Hump on the fretboard where the neck joins the body.
• Sunken top across the soundboard between bridge and fingerboard.
• The back of instrument looks very flat when it is dried out.
• Sharp fret ends extend beyond the edge of the fretboard.
• The plane of the neck angle on a dry instrument hits above the top of the bridge.

Symptoms of a wet acoustic instrument:

• High action. Strings that are unusually high off the fretboard, making it difficult to play.
• Unusually swollen top
• Unusual warp on the top, back or both at the end-block
• Improper neck angle. Sighting the neck to the bridge, the frets will appear to hit below the bridge.

Using patented technology, the D’Addario Two-Way Humidification System features disposable, moisture-filled packets with a breathable membrane that provides two-way humidity control, meaning it can either release or absorb moisture to consistently maintain a predetermined relative humidity (RH) level of 45-50 percent.

Final Notes on Humidity Control

To monitor the amount of humidity your instrument is receiving, we recommend the purchase of adigital hygrometer, a device that gauges and provides a read-out of humidity levels. It can be kept in the room where you store your instruments, or, better yet, in a central location inside the instrument case, preferably Velcro’d to the outside of the accessories compartment (facing the heel). The optimal range for your guitars and ukulele is 45-55% RH.

Below is some information from Taylor guitars regarding Humidity and how it can affect you instrument.

Essential products for instrument care and humidifcation are found HERE

Please read the following links from Taylor Guitars:
Symptoms of a Wet Guitar
Symptoms of a Dry Guitar
Using a Guitar Humidifier

Owners should be aware that problems can occur with any style of guitar but are more prevalent with higher priced & solid timber guitars.  As this is related to the guitars storage conditions it is not generally covered under normal purchase or repair warranties.