How to Varnish an Acrylic Painting with Polymer Gloss Varnish
Varnishing is the last step that protects a finished acrylic painting and brings back the depth and richness of the colours. With a water-based polymer gloss varnish the steps are simple: let the painting dry completely, brush on thin even coats, and give each coat a full day to dry.
How to varnish an acrylic painting: wait until the painting is completely dry, then remove any dust. Gently shake the bottle of Polymer Gloss Varnish and apply an even coat with a good flat-edged brush. Apply two to three coats, allowing 24 hours drying time between each coat. Wash the brush with soap and water straight after use. The varnish dries clear, flexible and non-yellowing, and is permanent and water resistant once dry.
Solid Solutions Polymer Gloss Varnish is a water-based professional gloss varnish for acrylic paintings on stretched canvas and canvas boards. It dries clear and stays flexible, archival and non-yellowing, and doubles as a gloss medium for acrylic paint. Australian made.
Shop polymer gloss varnish →Why Varnish an Acrylic Painting?
Acrylic paint dries to a durable film on its own, so varnishing is optional. Most painters still varnish finished work because it protects the surface and makes the colours look their best.
- Protection: adds a durable protective film over the paint that is permanent and water resistant once dry.
- Richer colour: a gloss varnish enhances colour vibrancy and brings back depth in darker areas.
- Even sheen: evens out patches where some colours dried glossier or duller than others.
- Moves with the canvas: the dried film stays flexible, so it suits stretched canvas that flexes over time.
| Quick reference | Solid Solutions Polymer Gloss Varnish |
|---|---|
| Base | Water-based polymer |
| Finish | Dries clear, gloss |
| Film | Flexible, archival, non-yellowing |
| Use on | Acrylic paintings on stretched canvas and canvas boards |
| Coats | 2–3 coats for best results |
| Between coats | 24 hours |
| When dry | Permanent and water resistant |
| Also | A gloss medium to mix into acrylic paint for extra gloss and flow |
| Clean up | Soap and water |
| Sizes | 250ml, 1 litre and 4 litre |
How to Varnish an Acrylic Painting, Step by Step
Let the painting dry completely
Only varnish when the painting is completely dry. Varnishing too early can trap moisture and affect the finish. Thin layers feel dry quickly, but thick or textured paint takes much longer to dry right through, so give heavy work extra time.
Clean the surface
Gently brush away dust, lint and hairs with a soft, dry brush. Anything left on the painting will be sealed under the gloss. Work in a clean, dust-free spot with the painting lying flat.
Shake the bottle gently
Give the bottle a gentle shake to get the right consistency. Shaking hard can add bubbles, so if you see foam, let it settle before you start.
Apply an even coat with a flat brush
Use a good flat-edged brush and apply an even coat across the painting in long, smooth strokes. Load the brush lightly, work from one side to the other, and don't go back over areas that have started to set. Remember the painted edges of the canvas.
Build up two to three coats
For best results apply two to three coats, allowing 24 hours drying time between each coat. Brushing each new coat in the opposite direction to the last helps you spot any areas you missed.
Clean up and let it dry
Wash your brush with soap and water straight after use, and keep the lid tightly closed. Leave the painting flat and undisturbed while the final coat dries.
Troubleshooting Your Varnish
Usually from shaking hard or brushing back and forth too much. Shake gently, load the brush lightly and finish each area with one light pass.
Coats that are too thick, a stiff brush or reworking areas as they start to set. Use a soft flat brush, thinner coats and fewer passes.
Often caused by varnishing before the paint is fully dry or by a coat that's too heavy. Always wait until the painting is completely dry and keep coats thin.
Clean the surface first and let it dry flat in a dust-free room. A clean box or sheet of card held loosely above the painting keeps airborne dust off.
Keep less varnish on the brush near the edges and varnish with the painting lying flat rather than upright on an easel.
Paints and surfaces behave differently. Try the varnish on a test piece or a small corner and let it dry before varnishing the whole painting.
Polymer Gloss Varnish as a Gloss Medium
Polymer Gloss Varnish isn't only a final coat. Mixed into Solid Solutions acrylic colours it works as a gloss medium, increasing glossiness and flow. It is well suited to glazing, where thin transparent layers of colour are built up over each other, and it can be applied as a sealant between layers of a painting.
Which Varnish Do I Need?
| Varnish | Best for | Finish |
|---|---|---|
| Polymer Gloss Varnish | Finished acrylic paintings on stretched canvas and canvas boards; also a gloss medium | Clear, flexible, archival gloss |
| Polyurethane Varnish (gloss or matte) | Wood, MDF, metal, plastic, concrete and other rigid surfaces, indoors and outdoors. Not for canvas or paper | Hard, tough, water and heat resistant |
| Mixed Media Medium & Varnish | Decoupage and collage: glue, sealer and varnish in one, on wood, paper, canvas and terracotta | Clear gloss |
Varnishing Acrylic Paintings: Questions & Answers
Do acrylic paintings need to be varnished?
It's optional, but recommended for finished work. Varnish adds a durable protective film that is permanent and water resistant once dry, evens out the sheen and enhances colour vibrancy.
What happens if you don't varnish an acrylic painting?
The painting is still stable, but the paint surface is left without a protective layer, and the sheen can look uneven where some colours dried glossier or duller than others.
What is the best varnish for an acrylic painting on canvas?
Use a water-based varnish that stays flexible, such as Solid Solutions Polymer Gloss Varnish. It's made for acrylic paintings on stretched canvas and canvas boards, and dries clear, archival and non-yellowing.
How long should I wait before varnishing?
Wait until the painting is completely dry. Varnishing too early can trap moisture and affect the finish. Thick or textured paint takes longer to dry right through than thin layers.
How many coats of varnish should I apply?
Apply two to three coats for best results, allowing 24 hours drying time between each coat.
What brush should I use to varnish?
Use a good flat-edged brush for smooth, even coats. Keep it just for varnishing so no old paint gets mixed into the finish, and wash it with soap and water straight after use.
Will the varnish yellow or crack over time?
No. Polymer Gloss Varnish dries clear and is an archival, non-yellowing professional artist grade varnish. The dried film stays flexible, so it moves with the canvas.
Can I mix polymer gloss varnish into acrylic paint?
Yes. Mixed with Solid Solutions acrylic colours it works as a gloss medium, increasing glossiness and flow. It is well suited to glazing and can be applied as a sealant between layers.
Can I use polyurethane varnish on a canvas painting instead?
No. Polyurethane Varnish is a hard varnish for rigid surfaces such as wood, MDF, metal, plastic and concrete. For acrylic paintings on canvas, use Polymer Gloss Varnish, which stays flexible.
Is polymer gloss varnish water-based?
Yes. It's a water-based polymer varnish, so brushes clean up with soap and water. Once dry it is permanent and water resistant.
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Protect your finished paintings
Solid Solutions Polymer Gloss Varnish in 250ml, 1 litre and 4 litre.