Acrylic painting · Oil painting ·

How to Varnish a Painting [Professional Tips]

How to varnish a painting blog banner

Once you’ve finished your first professional oil painting, an important step is applying varnish to keep your artwork protected against dust, dirt, UV rays, and yellowing. Not sure how to do it? Follow our steps below and keep your artwork in top condition.

What Is Varnishing & Why Is It Important

Typically, varnish is a blend of a solvent and a resin, creating a transparent and colourless coating that forms a strong bond with the painted surface. This thin protective layer acts as a guardian between your masterpiece and the atmosphere, ensuring its longevity.

Choosing the right varnish is crucial to achieving the desired finish for your artwork. If you want to amplify the vibrancy of the colours in your painting, opt for a glossy varnish. On the other hand, if you prefer a more subdued look, a matte varnish will gently soften the colours. The choice is yours, and it can make a world of difference in the final appearance of your artwork.

How To Varnish A Painting Step-By-Step

There are two ways in which you can apply varnish - by using a brush, or by using a spray can.

How To Apply Varnish With A Brush

Before you apply varnish to your artwork, make sure it is fully dry. Allow oil paintings to dry for at least 6-12 months, or until the surface is touch-dry for acrylics. Once the painting is ready for varnishing, follow our instructions step-by-step:

Make sure you have a clean, wide brush. (Either a Loxley Wide Bristle Brush or Skyist Varnish Brush).
Pour out the varnish into a dish – this way it is easier to control the amount of varnish you put on your brush.
Lay your work on a flat board.
Cover your work gently but quickly – apply long, even strokes covering the surface from top to bottom.
Work from left to right – slightly overlap each stroke.
Once you have left an area, do not go back over these areas until completely dry.
Remember the popular saying: 3 thin coats are better than 1 thick coat.
Leave the artwork to completely dry for 24 hours.

Hand dipping a paintbrush in oil paint varnish

How To Apply A Spray Varnish

The same rules apply for spray varnish as well – make sure your oil or acrylic artwork has enough time to dry before proceeding with varnishing.

Wipe over the surface of your artwork – make sure it is completely dry, and be careful what cloth you use.
Place your painting horizontally in a dust-free space – keep the surface flat at all times.
Shake the can for 10 seconds and then start spraying.
Apply the spray evenly about 30cm away from the surface.
Move from top to bottom, left to right – overlapping each layer slightly.
Work in thin layers – about 2 to 3 layers should be fine, but it is a personal preference. Between each layer, make sure the surface is completely dry.
Leave to dry for 24 hours.

Tips When Applying Varnish

Choose a dust-free area to work in and keep windows and doors open.
Wait until your painting is completely dry before moving or touching.
Leave to dry for 24 hours before moving or touching.
Make sure your artwork is on a flat surface and avoid working vertically.
If using a brush, use long, even strokes from top to bottom, moving gently and gradually from side to side.
If spraying, gradually spray from top to bottom, left to right, making sure you do not miss any area.
Avoid going back over areas that you have done. For any areas missed, allow the artwork to completely dry and then revarnish.

Best Varnishes For Artwork Longevity

At Loxley Arts, we stock professional-quality varnish that ensures the perfect finish for your masterpiece, keeping its colours vibrant for a long time even when hung at an exhibition. Here are our top recommendations:

Best Varnishes For Oil Painting

A traditional high-gloss resin-based varnish for use on oil and alkyd paintings.

Dries quickly and tends to darken with age.
Great for glazing – mix with the oil paint to increase transparency and speed up the drying time.
Can be removed for restoration with turpentine.
Apply as a top coat only when the oil paint is completely dried.

A gloss varnish which gives temporary protection to recently completed oil paintings whilst they are still drying.

Unlike normal varnishes, it is possible to paint on top of Retouching Varnish, which refreshes the colours so that they can be reworked later.
The varnish can be removed using white spirit if needed.

Gives oil paintings a quality permanent gloss finish.

Protective layer which prevents dust and moisture from getting into the paint.
The varnish is transparent and non-yellowing and can be removed for restoration work if required.
Apply the varnish only when the oil paint has completely dried.

How To Varnish An Oil Painting

The most important step to take care of when varnishing an oil painting is the timing. Oil paint dries by oxidation, which is a slow process. While a painting may feel "dry to the touch" in a few days, it can take anywhere from 6 months to a year or more for a thin painting to fully cure. Varnishing too early will trap the solvents and prevent the paint from properly hardening, leading to cracking and other issues.

Best Varnishes For Acrylic Painting

Prism Clear Glaze 150ml is a specially formulated, perfectly clear, non-yellowing glaze.

Can be used for paper, plaster and concrete
Gives a high gloss ‘porcelain’ finish.

Gives paintings a quality finish as well as a protective layer to prevent dirt and moisture from getting into the paint.

Clear, non-yellowing flexible coating which can be removed when restoration work is required.
Supplied in a 200ml handy aerosol, making it easy to apply in thin coats without getting build-up from overspray.

Gives maximum protection and gloss sheen to acrylic paintings.

Can be mixed with the acrylic paint or applied as a top coat when the paint is dry.
Permanent, flexible and durable gloss covering.
Can be used on 3-dimensional artwork and modelling materials.

How To Varnish An Acrylic Painting

Acrylics dry much faster than oils, meaning you can get to varnishing much faster. A thin painting may be ready to varnish in 24 hours, while a heavily textured or impasto painting may need up to a week to fully dry and cure.

What Is The Difference Between Solvent-Based And Water-Based Varnishes?

Solvent-based varnishes use organic solvents like white spirit, resulting in a stronger odour and longer drying times, but offering superior durability and a richer appearance.

Water-based varnishes use water as the solvent, providing a lower VOC content, quicker drying times, less smell, and easier cleanup, though they may have a slightly different aesthetic and potentially lower durability.

How Many Coats Of Varnish Should I Apply?

The number of coats depends on your chosen varnish and desired finish. We recommend:

Matt/satin varnish - 1–2 coats maximum
Gloss varnish - up to 3 coats
Spray varnish - up to 50 coats for an ultra-glossy look

Can I Paint Over Varnish?

Once you’ve applied your varnish layer, you should avoid going back and changing anything. Trying to paint over your varnish may disturb both the varnish layer and the paint beneath.

Keep Artwork Protected With Loxley Varnish

At Loxley Arts, we provide the paints, the brushes, the canvases, and most importantly, the varnish to ensure each masterpiece is not only showstopping but also stands the test of time. Browse our artist paints and find the best varnish for your chosen medium today!