<p>Traditional gouache is one of the more fragile mediums out there. It is unlikely it will preserve well when trying to seal it against repeated soakings as with coasters even using a varnish.</p>
<p>If you are using gouache for its solidly opaque, highly saturated and even matte finish any clear coat on top of the paint will change how it behaves optically and you will lose that effect.</p>
<p>There is however <strong>acrylic gouache</strong> which gives the same look as traditional gouache but is waterproof like regular acrylic paint. So it will be highly water resistant and not likely to bleed or change optically when adding a top layer like a clear coat of matte medium and/or varnish for protection. It does handle a little differently than traditional gouache in that it may dry faster and not be rewettable. Also watch out for it drying on the brush since you cannot dissolve it out of the bristles once it is dry.</p>
<p>Keep in mind that the final coat needs to be matte as well since a gloss finish will change how the pigmented surface interacts with light.</p>

CC BY-SA 4.0
2024-03-28T21:46:11.950Z
2024-03-28T21:56:08.053Z
2024-03-28T21:56:08.053Z
rebusB
<p>You could use a <strong>spray-on varnish</strong> and circumvent the problem altogether.<br />
Make sure to select a varnish intended for gouache, and let the coasters dry lying level to prevent any buildup from smudging the paint.</p>
<p>What's noteworthy as well is that varnishing gouache can dramatically alter the appearance of your work, as the varnish will deepen colours and increase the contrast.</p>

CC BY-SA 4.0
2024-03-28T17:03:42.837Z
2024-03-28T17:03:42.837Z
Joachim
<p>Has anyone experimented with varnishing or sealing gouache artworks on coasters? I'm concerned that since gouache is a rewettable medium, it might smudge and spread when in use. Additionally, I worry that applying varnish could pick up some of the paint with the brush.</p>

<painting><gouache>
How to varnish a gouache painting on a wooden coaster?
Shanan
# How to varnish a gouache painting on a wooden coaster?

(Asked by: username_0 on 2024-03-28)

Has anyone experimented with varnishing or sealing gouache artworks on coasters? I'm concerned that since gouache is a rewettable medium, it might smudge and spread when in use. Additionally, I worry that applying varnish could pick up some of the paint with the brush.

**Tags:** painting, gouache


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## 2 answers

### Answer by username_1 on 2024-03-28. Score: 2

Traditional gouache is one of the more fragile mediums out there. It is unlikely it will preserve well when trying to seal it against repeated soakings as with coasters even using a varnish.

If you are using gouache for its solidly opaque, highly saturated and even matte finish any clear coat on top of the paint will change how it behaves optically and you will lose that effect.

There is however **acrylic gouache** which gives the same look as traditional gouache but is waterproof like regular acrylic paint. So it will be highly water resistant and not likely to bleed or change optically when adding a top layer like a clear coat of matte medium and/or varnish for protection. It does handle a little differently than traditional gouache in that it may dry faster and not be rewettable. Also watch out for it drying on the brush since you cannot dissolve it out of the bristles once it is dry.

Keep in mind that the final coat needs to be matte as well since a gloss finish will change how the pigmented surface interacts with light.


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### Answer by username_2 on 2024-03-28. Score: 2

You could use a **spray-on varnish** and circumvent the problem altogether.  
Make sure to select a varnish intended for gouache, and let the coasters dry lying level to prevent any buildup from smudging the paint.

What's noteworthy as well is that varnishing gouache can dramatically alter the appearance of your work, as the varnish will deepen colours and increase the contrast.


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