Over time a painting can lose the original colours and visual impact through the perishing of traditional varnish or accidental spills and staining. As well as losing the display of a painting as the artist intended, a discoloured surface can also lead to loss of value and the danger of lingering contaminants or moisture penetrating the varnish layer. 

Why is my painting discoloured?

Discolouration of a painting surface can be caused by various factors. A yellow appearance may be due to traditional varnish deteriorating – old varnish is made from botanical ingredients and therefore decays over time causing a yellow or darkened appearance.

Fireplaces and candles are often the cause behind a darkened appearance – toxic particles from soot or smoke can become embedded and lead to a strong visual disturbance.

As many historic paintings have been on display over hundreds of years, it is likely that at some point in their life they have faced smoke contamination from fireplaces or nicotine.

Yellow hues can also be caused by nicotine contamination upon and within the varnish, building up over centuries or decades.

Paintings may appear clouded or with a light veil within the varnish, this can be caused by moisture becoming trapped or mould spores, this is often seen following a flood or escape of water which has affected the artwork. 

Varnish removal by trained conservators

Our conservators are trained to a museum standard and hold Masters degrees in their specialist fields. Our team will always take the appropriate steps to ensure the historic and artistic integrity of a painting, so as not to alter the cultural or monetary value during restoration.

Treatments and solutions are carefully selected to ensure the safe preservation of the painting, eliminating any risks with gentle testing of the surface before anything takes place. This includes shining a UV light upon the painting to see if there are any layers of unoriginal overpainting or previous alterations to the paint layer. 

Varnish removal can take several hours depending on the size of the painting, as small handmade cotton swabs are used for less than an inch at a time. A slow varnish removal process ensures that there is no cross-contamination, our conservators use precision to ensure the safety of the artwork at all times.

Following varnish removal, and after any further stained or discoloured painting restoration work is completed, a final layer of varnish is reapplied – this is a conservation-appropriate variety that is non-yellowing and UV reducing, allowing the painting to have ongoing protection into the future.

The finish of the varnish – matt, satin or high gloss – can be either the same as the original appearance or changed to help you see the artwork as clearly as possible.

Finding hidden features

During the varnish removal process, any paint which is unoriginal to the artwork may also come away. This often reveals missing or edited areas that have occurred over the course of its life, giving an insight into the history of the painting.

Removing surface stains

Varnish removal also eliminates any staining upon the surface of the varnish, including accidental marks, spills or disturbances. It can also remove layers of mould spores, soot and other contaminants.