Critchlow & Kukkonen Ltd

11 Apr 2025

Critchlow and Kukkonen Ltd offers conservation and restoration services for easel paintings from all periods in a variety of media and supports. We can treat paintings ranging in size from miniature to very large scale.

Our complete range of services include:

Conservation and restoration: detailed condition reports | surface cleaning | varnish removal | consolidation of paint layers | treatment of canvas distortions | tear mending | strip-lining & lining | filling losses | retouching | varnishing | conservation framing & glazing | preventative treatments | documentation & photography
Technical examination of paintings: ultraviolet light | binocular microscopy | pigment analysis
Preparation and documentation for exhibition & loan
Estimates and surveys of collections | advice for display and storage conditions | disaster response | talks and lectures.

Located in the south of Sheffield, the studio is easily accessible to visitors with small paintings as well as lorries delivering bigger works of art. The spacious studio and specialist equipment make it possible for us to treat very large scale paintings and carry out structural treatments including linings. We also make sure that any paintings in the studio are safe and have installed electronic and physical security systems that match museum specifications.

Conservation of a vandalised painting: Portrait of David Papillon by an Unknown Artist

This portrait from Leicester County Council’s art collection came to our studio in 2020. The vandalised painting had been attacked with a stanley knife and yellow spray paint, both of which had caused serious damage. The conservation treatment included consolidation of the paint layers, removal of spray paint and discoloured varnish, treatment of canvas deformations, tear repair and reattachment of the torn fragments, lining; filling and retouching, varnishing and conservation framing.

Front before treatment in raking light

The raking light image reveals the extensive damage caused by vandalism, including the tears and slashes to canvas and the severe canvas deformations.

Removal of spray paint

The spray paint was cleaned using solvents and cotton wool swabs. The spray paint had not damaged the varnish or original paint layers.

Tear repair

The large central area of canvas had been torn off but left behind in a long concertina shaped strip. This was carefully moisture treated to ease out deformations and reattached during the tear repair stage of treatment.

Front, after tear repair and before filling of paint losses

This image shows the painting following tear repairs, varnish removal, lining treatment and before filling and retouching.

Front after treatment

After the varnish removal, an isolating varnish was applied to protect the original paint layers. The extensive paint and ground layer losses were filled and retouched with dry pigments bound with a synthetic resin. The painting was then given a final varnish of synthetic resin.

Reverse before treatment

This image further highlights the severity of canvas deformations before treatment. The stretcher was also found to be in poor condition, with misaligned joints that were causing further deformations to the canvas.

Reverse after treatment

To support the complex tears, the painting was lined onto a secondary sailcloth fabric. The old stretcher was archived and a new stretcher was commissioned to better support the painting.

Accredited members

Lucy Critchlow ACR

Lucy was awarded the Institute of Conservation (Icon) Professional Accreditation for Conservator Restorers in 2014. Prior to the formation of Critchlow & Kukkonen Ltd, Lucy worked for Gillian Walker's Conservation & Restoration of Easel Paintings studio in Sheffield and undertook projects for museums and art galleries across the UK. After her History of Art BA (Hons) at the University of Birmingham, Lucy went on to achieve a Distinction at Northumbria University for the Conservation of Easel Paintings MA, and in 2010 she completed a post-graduate Conservation Internship at the Stichting Restauratie Atelier Limburg, Maastricht.

Eeva Kukkonen ACR

Eeva was awarded the Icon Professional Accreditation for Conservator Restorers in 2017. Before Critchlow & Kukkonen, Eeva worked in private conservation studios in Sheffield and Glasgow, and at SRAL, Maastricht, where she also undertook a post-graduate conservation internship. Eeva was part of the team conserving the walls and ceilings of the Scottish National Portrait Gallery. Eeva has first class master's degrees in the Conservation of Easel Paintings, Northumbria University (2012) and Approaches in Technical Art History (2010), University of Glasgow. Completed courses include Health and Safety for conservators; Pigments and the Polarising Microscope; Modern and Traditional Resins and Varnishes.

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