Our latest case study explores the restoration of a mid 19th century watercolour seascape, one of a pair and an original Luigi Renault of the Consul Kestner schooner.

Our client came to us rather concerned and discouraged after an antique expert concluded that it would be difficult to treat the painting.

The issue with our client’s watercolour is a common one for works on paper; pollutants had leached out from acidic and inappropriate backing materials.

It is a problem our conservators deal with on a regular basis. The acidic backing causes staining, noticeable in the vertical brown strips down the painting where the paper has been in long-term contact with the backing. This is particularly noticeable down the left-hand side of the painting, running down the sky and into the sea.

As with other watercolours that have had this problem, conservation would provide full stability to the seascape.


Our initial priority was to remove the inappropriate backing.  Unsuitable materials will have been used for paintings of a certain age when acid damage was not common knowledge.

Treatment begins with removing these materials, and once uncovered it’s possible to see the extent of the damage.

After discarding the backing materials, we continued the treatment by gently washing the watercolour in our solution to address the staining. This process also lifted dirt and contaminants on the surface of the painting.

Understandably sometimes our clients can be concerned when a wet treatment is required on a watercolour. But in much the same way we solvent test before cleaning and varnish removal for an oil painting, we conduct similar tests to guarantee the stability of the pigments. Therefore, our clients can be assured that there will be no changes to the pigments – the colours will only brighten as the dirt is lifted.

Our treatments continued to address and remove the staining, and once complete the painting was considerably improved. The watercolour was mounted onto appropriate non-acid materials and re-installed in the frame. The frame itself was not harmful to the painting and provided the necessary support.

Our client was delighted to receive her painting back home, and commented, ‘I was really pleased, it looks great. The whole painting shows up all the detail now and is full of life.’

Works on paper are much more fragile than paintings on canvas or panel, but with the right care and treatments, they can be successfully conserved in exactly the same way.

It was very satisfying to be able to reassure our client that restoration would be successful and address her understandable concerns. This special painting was entrusted into our care, and it was a pleasure for our team to have this seascape painting ship-shape and sailing smoothly once more.

If you have a watercolour or similar work-on-paper that needs conservation, please get in touch with our team for no-obligation advice.