Adding the right varnish, in the right way, is a sound investment to ensure your finished oil or acrylic painting stays looking its best. Varnish protects the painting from dirt and dust and evens out the painting’s final appearance, making it all equally glossy or matt.
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.
Fixing dull paintings
If your painting is dull, it is easy to confuse the need for varnishing with the dullness created by colour that has sunk into the surface. If the colour has sunk then varnishing should be avoided. Instead, you should “oil out” those sunken areas using Artists’ Painting Medium. You can read our article on oiling out here.
Sometimes artists varnish their work to help stabilise surfaces with added texture or damaged layers. But while varnish will certainly help with this, once the varnish is on it cannot be removed without damaging the work. If you have pictures like this, we recommend you keep the varnished work behind glass and think about how to improve your technique for the future.
What types of finished surfaces can be varnished?
Varnishes work well with oil and acrylic because the paint films are relatively thick and separate from the surface.
Varnishes do not work well with gouache, watercolour and drawings, because they will be absorbed by the paint and/or paper, becoming an integral part of the picture. This could cause discolouration. Additionally, varnish on drawings and gouache or watercolour works cannot be removed.
Generally, artists choose varnishes for the sheen they provide, or because they have been used by their 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 chosen because they give the brightest, deepest colours. But works with gloss varnish have a lot of reflection.
- Matt varnishes avoid reflections but the colours appear duller.
All Winsor & Newton varnishes can be used on oil, alkyd, water mixable oil or acrylic paintings. But all are designed with specific types of colour in mind.
The Winsor & Newton varnishes
For oil colour
Dammar Varnish: The oldest liquid varnish, giving 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 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: The most popular varnish, also providing a very high gloss finish. Stronger solvents will be needed to remove it as time goes by.
Professional Matt Varnish: One of the most modern varnishes, this 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 mix of about 50:50 to achieve a satin finish.
Professional Satin Varnish: A superior quality UV resistant satin varnish, removable with Artists’ White Spirit or Distilled Turpentine.
Retouching Varnish: 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: These varnishes are formulated avoiding conventional solvents, making them ideal for communal studios or 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: These 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.
Top ten tips when applying varnish
- Wait until your painting is completely dry.
- Choose a dust free area to work in, keeping windows and doors closed.
- 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.
- Keep the work to be varnished flat on a table or work surface – avoid working vertically.
- 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.
- 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”.
- Leave to dry for 24 hours. If a second coat is required, apply it at a right angle to the first.
Handling and hanging
It’s best to avoid leaning varnished paintings together, as they may stick. If you use bubble wrap around your varnished painting, or pick it up with your fingers touching the varnish, impressions may show in the varnish. Avoid hanging pictures in bathrooms or kitchens, or above radiators or open fires, as they will get dirty very quickly.