Do you know how long it takes for your paints to expire? All paints have an expiration date, but some last longer than others. Oil paints, for example, have an extremely long shelf life of around 40 years, allowing these paints to last longer than other paints such as acrylics and watercolors.
So, does gouache paint expire? Gouache paint has an average shelf life of around 2 years however, you can rewet the paint if it dries out and no mold is detected. Because of its ability to grow mold, gouache certainly has an expiration date, even when the paint appears fine.
In this article, I explain why gouache paint expires quickly, how to extend the lifespan of your gouache paint, how to preserve gouache paintings, and more.
Gouache Paint Expiration
Gouache is a water-based paint that mixes natural (or synthetic pigments) with water and gum arabic. Because of its water base, many people assume that gouache paints last a long time. Despite this assumption, gouache expires after around 2 years.
My favorite and top pick is always Arteza Gouache Paints. They have so many different colors, and the quality is amazing! I usually use Arteza paints for all of my projects.
The reason why gouache paint expires so quickly is that it can easily harbor mold growth. Whenever oxygen is mixed with the paint, mold can grow within the tube. Every time you open the tin or tube, you risk exposing the paint to oxygen, leading to bacteria, fungus, and mold in the future.
As a result, gouache paint lasts for about two years, give or take a year depending on how quickly the mold develops.
Ways to Extend the Shelf Life
If you think you need to throw away your gouache paint because it hardened, think again. Simply adding water to the paint will revitalize it so you can continue to paint with the gouache.
Even when the paint is moist, you may need to toss it out due to mold growth. The best way to prevent mold growth is to ensure that the paint caps or lids are screwed on tightly. This will help fight oxygen exposure and mold growth.
Another way to extend the shelf life of your gouache paint is to mix it with honey. Honey is a natural mold and bacteria deterrent. By mixing honey with the paint, less mold will grow. Not to mention, it adds a bit of texture to the paint, makes it easier to spread, and fights drying. You can also add honey to acrylic paints.
Finally, the last way artists extend the lifespan of their gouache is by adding glycerin into the paint. I recommend using this Kosher Premium Glycerin, to mix the gouache paint with. This will not extend the drying time of the paint, but it will allow the paint to remain sticky for longer. You can add a few drops of ammonia as well, which will help fight mold.
How Long Do Gouache Paintings Last?
The lifespan of a gouache painting depends on the quality of the paint, and how you choose to seal or showcase your painting. Even some of the lower quality paints will last longer than many watercolors. Still, it’s important to select high-quality paint and seal the painting correctly to maximize its longevity.
Another great brand is MagicFly. I also use their gouache paint tubes, and the quality is amazing. They’re non-toxic and premium quality.
Theoretically, gouache paintings can last centuries if the quality of the paint is good, and if they are sealed correctly. We will discuss preserving and sealing gouache paintings later in this article, that will help you understand how to preserve your final product.
Even lower quality paints can still last a good while. For example, we have personally used lower quality gouache paints that have resulted in 15-year-old paintings and counting. Of course, we used a fixative on these paintings, which explains why they are still in good condition.
HIMI is another option if you want to go with a lower quality, and not premium based gouache paints. This option is great for beginners or even kids to experiment with.
How Do You Preserve a Gouache Painting?
Traditionally, gouache paintings were preserved through glass framing. Glass frames are still the optimal way to preserve a gouache painting. If you are a professional who needs the painting to last well beyond your lifespan, glass frames are ideal.
The downside of glass frames is that they are incredibly expensive and more difficult to come by. For amateurs who want to keep the paintings for themselves, you might want to opt for a different option purely based on affordability.
Varnish is a much more cost-effective option. The only reason why varnish is not used by professionals is that it can affect the darkness, depth, and finish of the painting. It also prevents the artist from retouching the painting at a later point.
To seal all my paintings, I always use Krylon Sprays. They protect your painting from flaking, chipping, and even UV rays. They even have glossy or matte finish options.
If you do not use a fixative or seal the painting, however, a gouache painting can easily be ruined due to excess moisture or an accidental spill. If a lot of water falls upon your painting, the painting will essentially be ruined.
Ultimately, it is up to you to determine which preservation technique is right for your painting. If you are a professional who needs superior quality for your painting, a glass frame is the best technique. For more amateur purposes, a varnish will be a much more cost-effective option.
Does Gouache Need to Be Sealed?
Yes. Gouache needs to be sealed because water can easily dilute painting. Any time there is a spill or excess moisture in the air, the water can damage the quality of the painting.
Sealing the gouache ensures that the painting can withstand spills and other issues. You can either seal the painting with a glass frame or a varnish.
How to Seal Gouache
Sealing your gouache painting extends its lifespan and protects it from any water damage. If you want the most professional final look, using a glass frame, like this one here, is the proper way to seal gouache paintings.
If you cannot afford to protect your gouache painting with a glass frame, you can opt for the varnish method we discuss above instead. The varnishing method is ideal for someone who wants to protect their painting for themselves or maybe a child.
I personally have used both methods. A glass framed painting always looks much more elegant, and adds a person touch to your home decor, but a gloss sprayed painting can also be just as nice anywhere.
Varnishing your painting will require a bit more effort, but the process is relatively easy. You begin by applying one layer of varnish that seals the painting’s surface. Apply the spray from about 3-6 inches away form he surface. This will essentially waterproof the painting and is non-removable.
Once the first coat has dried, apply a second layer of isolation coat. This prevents the painting from yellowing and adds an additional layer of protection to the painting. This layer is also nonremovable. Finally, add a third layer of removable varnish. This varnish will allow anyone in the future to replace this layer without damaging the painting’s surface.
Final Thoughts
Even though dried gouache paint can easily be revitalized by adding water, gouache paint as a whole only has a lifespan of two years. Because the paint can grow mold every time oxygen is introduced to the tube, gouache paints should be thrown away after two years.
You can try to preserve your gouache paints by keeping the tubes closed tightly or mixing honey or glycerin with the paint.
Professional artists should seal their gouache paintings with a glass frame, but you can also opt for varnish instead. Both of these options will protect the painting, allowing it to last decades, if not centuries.
Don’t forget to check out my other articles for all your painting Q&A’s. Happy painting!