Ever wondered why your guitar plays amazing on some days but then feels like a completely different instrument on another? Guitar humidity or temperature could be the culprit!
Did you know that there is an optimum temperature and humidity range that your guitar should be kept at? And did you also know that if you fail to keep an eye on these levels, the damage could be irreparable? Yeesh!
Damage caused by humidity and/or temperature is not covered under most manufacturer warranties either, so it’s extra important to know how to manage these potential guitar killers!
In this article, you’ll learn how humidity and temperature affect a guitar, the safest conditions for storing your instrument, and how to hopefully prevent any issues before they actually happen!
Table Of Contents
- Acoustic Guitars vs Solid Body Guitars
- How Does Temperature Affect A Guitar?
- How Does Humidity Affect A Guitar?
- How Does High Humidity Affect A Guitar?
- How Does Low Humidity Affect A Guitar?
- Frequently Asked Questions
Acoustic Guitars vs Solid Body Guitars
The style of guitar will play a big role in determining the degree to which it is affected by humidity and/or temperature.
A solid body guitar, such as a Stratocaster, is not massively affected by temperature or humidity. This is because the more substantial, solid blocks of wood used in its construction will offer better resistance to changes in atmospheric conditions in most instances.
The solid bodies of most electric guitars are unlikely to exhibit any warping, although you may experience other climate related issues such as bowing of the neck, fingerboard shrinkage, and corrosion of metal parts.
On the other hand, a hollow-body instrument, such as an acoustic guitar is much more likely to be affected by temperature and humidity.
This is because acoustic guitars are essentially comprised of thin sheets of wood and a lightweight wooden framing. These slim pieces of wood are easily affected by changes in climate.
In addition, acoustic guitars are held together by a whole lot of glue, while solid body guitars are generally screwed together. Which of these do you think is going to be more sensitive to climate related issues? That’s right, the glue!
As acoustic guitars (especially the more expensive ones!) are clearly more affected by temperature and humidity than solid bodied instruments, we will mainly be talking about acoustics and other hollow-body instruments throughout the rest of this article.
How Does Temperature Affect A Guitar?
As temperature increases, the woods used in the construction of a guitar will expand. Conversely, as temperature decreases, the woods will contract. This process can result in warping and distortion of the wood, which could potentially lead to permanent and irreparable damage!
A gradual or small temperature change is unlikely to cause lasting damage, as the wood is generally able to adapt to these conditions.
However, exposing the guitar to a large and sudden temperature change is likely to ‘shock‘ the wood, and, as a result, warping may occur.
An example of this type of scenario might be if you have accidentally left your guitar overnight in the car trunk during winter. If you were to bring that guitar into your warm home from the potentially freezing conditions outside, that huge swing in temperature is not going to do much good for your instrument!
A move like this could likely cause hairline cracks in the guitar’s finish – also called ‘checking‘. The only way to repair this would be a complete refinish!
In the worst case scenario your guitar might not even make it out of the trunk! If the weather is cold enough, the wood might shrink to such an degree that parts might separate entirely. Check out this insane photo from WorldMusicSupply – yikes!
In general, don’t travel with your guitar in the car trunk at all. Keep it on a passenger seat where it is less likely to experience extreme temperature fluctuations.
On the opposite end of the spectrum, exposure to very high heat could even cause the glues used to hold your guitar together to melt – eek!!
What Is A Safe Temperature For A Guitar?
In general, you should try to keep your guitar within a ‘safe’ temperature range of 32-95 degrees Fahrenheit (0-35 Celsius). However, the ideal temperature for a guitar is somewhere between 65-75 degrees Fahrenheit (18-24 Celsius).
In terms of moving your guitar from one place to another, try to keep the difference in temperature to no greater than around 20 degrees Fahrenheit (7 Celsius) if possible.
How To Limit The Effects Of Temperature On Your Guitar
There are a few ways that you can try to limit the effects or damage that a swing in temperature might have on your guitar.
- Firstly, you can pay close attention to the condition of your instrument. Check for cracks, warping, and other temperature-related issues, and contact your local guitar tech to get on top of the issues before they become too serious to repair.
- Try to avoid a sudden change in temperature of more than 20 degrees Fahrenheit (7 Celsius) if you can.
- Steer clear of extreme temperatures of less than 32 Fahrenheit (0 Celsius) or more than 95 Fahrenheit (35 Celsius).
- Use your heating or air conditioning systems to maintain an acceptable temperature in your guitar room, but keep your guitars a good distance away from the units themselves!
- Keep your guitars away from direct sunlight/windows and air ducts.
- Your case or gig-bag can somewhat act as a buffer from atmospheric conditions (up to a point!), so keep your guitar in there when not in use. A TRIC case is best – find out more about these at the end of this article.
If you’ve ever run a fish tank, you’ll know that the aquarium will give you your new fish in a plastic bag containing water from the tank they came from. In order to make the transition as stress-free as possible, the sealed bag is placed in the new tank so that the temperature can slowly equalize. Then water from the new tank is gradually added to the bag little by little, to allow the fish to get used to the new water quality. And only then is it finally released into its new environment.
You should treat your guitar the same way! Except the fish is your guitar, and the bag is your hard case.
Erm…not quite right…but you get my point, right? PS, I bet if you’re just skimming this article you stopped here to find out what in the hell the fish in the case was all about. Read the whole article, you’ll learn a lot!
Read more about this guitar acclimatization process at the end of this article.
How Does Humidity Affect A Guitar?
As humidity increases, the tonewoods used in your guitar will swell. And conversely, as humidity decreases, the woods will shrink.
Failure to maintain optimal levels of moisture in your guitar can result in many issues, including, but not limited to protruding frets, cracking in the woods, fret buzz, a sunken top, and the bridge may also lift up on an acoustic. The list goes on and on!
These issues will obviously have a large effect on the playability and tone of your guitar.
Although a gradual change in acoustic guitar humidity is unlikely to have a major effect, a large and sudden change will almost definitely adversely affect your instrument.
For example, if you lived in New Orleans (where humidity averages 86%), and flew to perform a few shows in Las Vegas (30% humidity), your guitar is definitely going to have a bad time! If you don’t correctly humidify it, the woods will begin to dry out and shrink – this is referred to as a ‘dry guitar‘.
If you were to go the opposite way and travel from an arid, dry area to somewhere with a high level of humidity, your guitar’s woods will absorb the moisture from the air and expand. When a guitar has absorbed too much moisture it is referred to as a ‘wet guitar‘.
What IS Humidity?
Humidity is the measurement of the volume of water vapor contained within the air. As temperature increases, so too does the volume of water vapor that can be held by the air.
When you are listening to the daily weather report, when they talk about humidity they will be referring to relative humidity. This is the volume of water held in the air, in relation to the maximum amount of water vapor.
When I talk about humidity percentages in this article I am referring to relative humidity. If you decide to use a hygrometer (more about these later) to measure the humidity in your guitar room/case, it’s useful to know that these will display relative humidity also.
What Is The Best Humidity Level For A Guitar?
Most luthiers and guitar techs agree that the ideal humidity range your acoustic guitar should be exposed to is between 45% and 55% relative humidity. Extended exposure to levels outside of this range can lead to potential issues and/or damage to your guitar.
Martin and Taylor maintain their factories within this range to ensure that their instruments get off to the best possible start. Once the guitars leave the factory it’s up to you to follow suit!
Luckily, the recommended comfortable humidity level for your home is also between 45-55%, so for most people, maintaining a good environment for your guitar shouldn’t be too difficult.
How Does High Humidity Affect A Guitar?
What Is A Wet Guitar?
A wet guitar is an instrument that has absorbed too much moisture. Usually, this occurs after it has been exposed to an area with very high humidity (80-90%) for several weeks. It can also happen after living in an area with medium to high humidity levels (70-80%) for several months.
Unfortunately, a wet guitar can also occur as a result of guitarists being overzealous with humidifiers. In trying to protect their instruments from drying out in arid climates they actually end up over-humidifying them. Oops!
High Humidity Guitar Damage Symptoms
Although high levels of moisture will not usually crack the wood in the same way that lower levels will, the effects are just as serious and can end up costing more to fix.
Symptoms of high acoustic guitar humidity damage (or a wet guitar) include:
- The back or top of the guitar becomes swollen. Be careful, as some guitars do have an arched back/top by design!
- The fretboard is wider than the neck, leaving a ‘step’ where they meet.
- High string action due to the swollen top wood.
- Incorrect neck angle.
- Tone is less vibrant and dynamic, largely due to the swollen top now having a more limited movement.
- Strings may exhibit rust, or wear out much faster.
- Corrosion on jacks, pots, switches, and other electrical parts.
- In extreme cases, you may also notice mold and mildew.
How To Prevent Or Fix A Wet Guitar
As I’ve already mentioned above, the effects of a wet guitar can be more pricey to repair, so let’s look at how we can hopefully avoid these symptoms in the first place!
1. Firstly, you can consider using a humidification system designed specifically for guitars. These work best in areas that don’t have a high moisture level throughout the entire year.
A simple, and cheap solution is the Humidipak Two-Way Humidification System from my friends over at D’Addario. This clever product is placed inside your guitar’s case and maintains a constant, ideal humidity level of between 45 and 50% by adding or removing moisture as necessary.
This makes maintaining optimum acoustic guitar humidity levels super easy, as it removes all guesswork on your part.
2. If you live in an area with high levels of humidity all year round, you can also try using silica gel packs or bamboo charcoal kits. Place these inside your guitar case to absorb moisture, and replace them every few months.
3. In addition to one of the two solutions above, you can also use a dehumidifier in the room where you store your guitars. This is a good idea if you have multiple guitars that you need to protect. As a bonus, the dehumidifier will also make the room a more pleasant place for you to hang out in.
4. One last step you can take is to occasionally take a hair-drier to the inside of your case to help remove lingering moisture. Make sure to take the guitar out first!
Best Hygrometer For Guitar
In order to ensure that you don’t remove too much moisture using method 2 or 3, also make sure to pick up a digital hygrometer so that you can monitor your acoustic guitar humidity levels.
Handily, D’Addario also makes an excellent Bluetooth-equipped hygrometer that will notify your phone if there is a spike in humidity or temperature. In addition, it will also notify you if your guitar suffers an impact. You can find out more about the Humiditrak Hygrometer here.
Alternatively, if you’re happy to manually check on the humidity levels, you can pick up a good hygrometer from as little as $10. For example, click here to check out the best selling model on Amazon.
If it’s too late and your guitar is already suffering the effects of being over-humidified, then 9 times out of 10 all you need to do is expose it to the ideal moisture levels for a few days and the issues should hopefully resolve themselves. Do this using one or more of the methods above.
How Does Low Humidity Affect A Guitar?
What Is A Dry Guitar?
A dry guitar is an instrument where the woods used in its construction have low levels of moisture, resulting in potentially serious damage to the guitar. Usually, this occurs when it has been exposed to an area of very low humidity (under 40%) for a prolonged period of time.
It can also arise as a result of guitarists going overboard with a de-humidifier in the room. In their well-meaning efforts to counteract the high humidity where they live, they actually end up removing too much moisture from the air and drying out their guitars!
This is why you need a hygrometer!
Low Humidity Guitar Damage Symptoms
Symptoms of low acoustic guitar humidity damage (or a dry guitar) include:
- Sharp fret ends extended beyond the edge of the fingerboard.
- Neck bow.
- A hump on the fingerboard where it meets the body.
- The guitar top has sunk.
- The guitar back appears very flat.
- The bridge has lifted from the body.
- Lower string action/fret buzz.
- Cracking of the neck and/or body woods.
- Cracking in the finish of the guitar.
- Separation of joints.
- Tone is less vibrant and dynamic.
How To Prevent Or Fix A Dry Guitar
As the effects of a dry guitar can be very serious, it is important to take preventative steps to ensure that you don’t ruin your instrument.
1. As I already pointed out above, one of the simplest methods to prevent humidity-related issues is through the use of a guitar-specific humidification system.
I highly recommend the Humidipak Two-Way Humidification System from D’Addario, which will magically maintain optimum moisture levels of 45-50% for you. This is a very simple and affordable option that takes all of the guesswork out of this task. Simply place the packs in your case or gig-bag and you’re good to go. It’s a no-brainer really.
Other similar products are available that suspend a damp sponge inside your acoustic guitar’s sound-hole. These work okay, but need re-moistened every few days, and also cause a humidity spike when the sponge is newly wet. Plus you will have to manually monitor humidity levels yourself to ensure you aren’t overdoing it.
2. You can also use a room humidifier to add moisture to the area that you keep your guitars in. This can be a great option if you have multiple guitars in the same room that you’d like to protect.
Make sure to also pick up a digital hygrometer so that you can monitor humidity levels in the room. You don’t want to add too much moisture and end up with a wet guitar instead! See my hygrometer recommendations in the section above.
If you’ve left it too late and your guitar has already dried out, then 9 times out of 10 all you need to do is expose it to the ideal moisture levels for a few days and the issues should hopefully resolve themselves. You can do this using one of the methods above.
To sum up, in order to avoid potentially irreparable damage to your guitar, please try your best to ensure that you don’t expose it to large changes in temperature and/or humidity wherever possible.
It’s pretty easy to do and could help you avoid some pretty hefty repair bills. All you need to do is maintain a consistent humidity level – simple!
A small investment into an acoustic guitar humidity controlling system (like the one mentioned above) will go a long way to ensuring that your instrument plays its best for many, many years to come.
If your guitar is already suffering the effects of a change in climate, simply exposing it to optimum humidity levels for a few days may just be enough to bring it back to life!
Frequently Asked Questions
How Should I Transport My Guitar?
Remember my fish tank analogy above? Do this! If moving your guitar from one climate to another, transport it inside of its case. The case will act as a buffer and allow the guitar to acclimatize more gradually.
When you reach your destination, let the guitar hang out for a while inside of the case. After some time, crack open the case a tiny amount, and then later on, open the case fully. Although this is a slight pain in the ass, it should help prevent the woods from being shocked due to sudden exposure to the new environment.
Also, make sure to keep a product such as the D’Addario Humidipak inside the case during transport to help maintain good humidity levels.
Are Some Woods More Stable Than Others?
Some tonewoods used in the construction of guitars are less susceptible to the effects of changes in humidity and temperature. For example, roasted maple has been ‘baked’ to remove moisture and make it much more stable.
The way that the wood has been cut will also determine how much your guitar will be affected by climate. For example, quarter-sawn woods are generally much more stable than flat-sawn examples.
You can find out more about the qualities of different tonewoods in my huge guide.
Does A Guitar Sound Better When It Dries Out?
No! There is a common belief that as a guitar dries out it will sound better, when the truth is actually that it will just crack. This myth came about due to confusion with a guitar’s natural aging process, where the hardening of the wood causes the guitar to sound more dynamic and have extra volume.
What Guitars Need To Be Humidified?
All of the guitars that you’d like to protect should be humidified, especially the newer ones! This is because most modern guitars use kiln-dried wood to try and speed up the aging process. Unfortunately, this drying method also results in a wood that is less stable and requires additional moisture to prevent warping.
Does A Guitar Case Protect From Humidity?
To a degree, yes! A hard case will provide a good level of protection against temperature, humidity, as well as physical impacts. It will take some time for the outside climate to reach the interior of your case, so it is generally a good idea to keep your guitar there when not in use.
A gig bag will not offer the same level of protection, but is better than nothing!
Godin makes an excellent option called the Thermally Regulated Instrument Case (TRIC), which is specifically designed to offer increased protection against humidity and temperature changes. You can check it out here on Amazon.
Should I Humidify My Electric Guitar?
Many guitarists do not feel the need to humidify their solid-body electric guitars, claiming that the solid slabs of wood are less affected than the thin sheets of wood used on hollow-body guitars. While this is true, humidity can still cause issues such as neck bowing, fretboard shrinkage, and corrosion of metal parts.
So if it’s an electric guitar that you really want to protect, it is still worth taking the effort to humidify it. After all, one of the kits mentioned above is only going to set you back 25 bucks – where’s the harm?
Is AC Bad For Guitars?
As long as temperature and humidity are within the accepted ranges, then your air conditioning will not harm your guitar. The exception will be if you place your guitar right next to the air conditioning duct itself.
We had an issue at the store I work at a few years ago. The shop-floor staff had accidentally placed some new guitars right next to the AC – the frets actually popped out of the fingerboard!
Is It Bad To Take A Guitar Outside?
Obviously, you won’t want to be playing guitar in the rain, but there is no danger to taking your guitar outside on a sunny day. Just try to limit the exposure time to a minimum and keep your guitar in its case or in a shaded area when not being used.