How to treat mould in oil paintings
For any art collector, the appearance of mould on oil paintings is concerning. Not only is it unsightly and detrimental to the enjoyment and appeal of the painting, but if left untreated it can spread to other areas of the canvas and cause significant damage.
When a painting is stored in a damp, dark and humid location, the conditions are perfect for an outbreak of mould.
If you have recently suffered a flood, or your paintings have obtained water damage, this can also lead to mould growth.
If you discover that your painting has been affected by mould, you should refer to a professional conservator for treatment. While the painting is still at home, refrain from touching the affected areas or wiping the mould. This can cause the mould to contaminate other areas of the painting and will require further restoration. The artwork should also not be kept in close proximity to non affected artworks and applying bleach or vinegar-based products to the painting is strongly advised against.
Once the painting has been assessed by a conservator and the scale of mould has been analysed, treatment in the studio can then commence.
The reverse of the painting can be misted with 70% alcohol in water. This mixture will desiccate and kill the active mould. A spray is used to dampen the canvas, for example with a fine mist, rather than applying with a cloth or brush.
For mould on the surface of the painting, a suitable solution, such as the alcohol and water mix, can also be used after ascertaining the scale of the damage. Crucially, non-invasive tests will be conducted to determine the efficacy of the treatment.
To remove the dry mould off the paintings, a soft bristled brush is used to gently loosen the particles without interfering with the paint layer or spreading the mould to other areas. A Museum Vac with a HEPA filter (high efficiency particulate air) is used alongside the brush. This is a specially designed conservation product to safely remove mould and mildew spores, fungi, and other irritants safely and without risk to the painting or conservator.
Completing a professional solvent-based clean is also recommended to fully revive the painting after the mould is eradicated.
When an oil painting is damaged by mould, it is inevitable that the frames and stretcher bars will also be affected. Treating mould in wood is different than on canvas, but it can still be achieved in the studio. Alternatively, we can obtain new stretcher bars, and if the frame is badly damaged we can provide our recommendations on new frame options.
For more advice on the preventative measures you can take to look after your painting, including the most suitable environmental conditions, you may find it helpful to read How To Store and Display Your Artwork.