To ensure your finished oil or acrylic painting stays looking their best, adding the right varnish, in the right way, is a sound investment. Not only does varnish protect paintings from dirt and dust, it can even out the painting’s final appearance with either a glossy or matt finish.
Over the years, dirt and dust will stick to the varnish, rather than the painting. When the time is right, the varnish itself can be removed and the painting re-varnished to make it look as good as new. Read on for expert answers to frequently asked questions on varnishing paintings.
At what stage can I varnish a painting?
You’ll need to wait until your painting is completely dry before adding varnish to it.
Where should I work when applying varnish?
Choose a dust-free area to work in, keeping windows and doors closed. It’s best practice to varnish on a flat table or work surface – avoid working vertically.
What kind of brush is recommended?
Use a flat, wide, soft and tightly packed varnishing brush, such as the Winsor & Newton Monarch Glazing Brush. Keep it clean and use it only for varnishing.
How do I apply the varnish?
Stir the varnish well and pour it into a clean, flat saucer or tin. Load your brush, then wipe it on the side of the saucer so it is not dripping. Then, apply the varnish in one to three thin coats, rather than one thick coat.
Use long, even strokes from top to bottom, moving gradually from one side to the other. Remove any bubbles. Avoid going back over areas that you’ve done. For any areas you’ve missed, simply allow the piece to dry completely and revarnish.
After you’ve finished, shield the work from dust with a protective plastic film known as a ‘tent’.
What types of finished surfaces can be varnished?
Varnishes work well with oil and acrylic. Their paint films are relatively thick and separate from the surface.
Varnishes don’t work well with gouache, watercolour and pencil drawings. The varnish will be absorbed by the paint and/or paper, becoming an integral part of the picture, and this could cause discolouration. Furthermore, you won’t be able to remove varnish on gouache, watercolour or pencil works.
Which varnish should I use?
As with anything, each artists has their own preferences. You could choose a varnish for the sheen it provides, or because it has been used by your favourite painters. Here’s a brief overview of the different kinds of varnishes:
- Dammar remains one of the most popular varnishes, even though newer ones have been introduced since its development.
- Gloss varnishes are often chosen because they give the brightest, deepest colours, but they also have a lot of reflection.
- Matt varnishes avoid reflections but the colours appear duller.
How can I fix a dull painting?
It’s easy to confuse the need for varnishing with the dullness created by colour that has sunk into the surface. A useful tip: if the colour has sunk, varnishing should be avoided. Instead, try to ‘oil out’ those sunken areas using Artists’ Painting Medium. You can read our article on oiling out here.
In other cases, artists varnish their work to help stabilise surfaces with added texture or damaged layers. While varnish can certainly help with this, once it is on it can’t be removed without damaging the work. It’s recommended you keep the varnished work behind glass, and consider other ways in which you can improve your technique for the future.
How long should I leave the varnish to dry?
Twenty-four hours. If a second coat is required, apply it at a right angle to the first. When going to handle the painting, wait until it is completely dry.
How should I handle and hang my varnished paintings?
Make sure to keep varnished paintings separate from one another when handling – it’s best to avoid leaning them together, as they may stick. Also steer clear of picking up the varnished works with your fingers, touching the varnish or using bubble wrap on them as impressions may show in the varnish.
When displaying varnished paintings, it’s best to hang them on walls or surfaces away from bathrooms, kitchens, above radiators or open fires so as not to dirty them quickly.
Winsor & Newton varnishes
All Winsor & Newton varnishes can be used on oil, alkyd, water mixable oil or acrylic paintings, and each are designed with specific types of colour in mind.
For oil colour
- Dammar is the oldest liquid varnish. It gives a very high gloss. Winsor & Newton is the traditional ‘5lb cut’ if you want to use it with mediums (we do not recommend this, but millions of artists do it). As Dammar is a strong varnish, we recommend using Distilled Turpentine, our strongest solvent, when it needs to be removed.
- Professional Gloss Varnish is the most popular varnish. It also provides a very high gloss finish. Stronger solvents will be needed to remove it as time goes by.
- Professional Matt Varnish is one of the most modern varnishes. It is easy to remove and gives a medium matt sheen. Professional Matt and Gloss varnishes can be intermixed to achieve varying sheens. We suggest a 50/50 mix to achieve a satin finish.
- Professional Satin Varnish is a superior quality UV-resistant satin varnish, removable with Artists’ White Spirit or Distilled Turpentine.
- Retouching Varnish is a UV-resistant gloss varnish which gives temporary protection to recently completed oil paintings. It’s quick drying and should be used in thin layers.
For Artisan Water Mixable Oils
- Artisan Gloss, Matt or Satin varnishes are formulated avoiding conventional solvents, making them ideal for communal studios or for those needing to avoid hazardous solvents. These varnishes can be used on conventional as well as Artisan oil paintings.
For acrylic colour
- Professional Acrylic Gloss, Matt or Satin varnishes are uniquely formulated to be removable and contain UV resistance. The satin varnish gives a mid-sheen finish, in between the matt and gloss varnish finishes. The Galeria Acrylic range also has its own collection of gloss, matt and satin varnishes.