Each stained-glass windows is restored in our workshop. Before being removed from its original home an accurate photographic record is made which shows the exact design and size of the frame.
The stained-glass window is then reinforced by applying adhesive film to the outer side. Then, it is carefully packed and transported to the workshop, where it is carefully examined to assess the condition of the ‘grisaille’ work, the came, and the broken or missing glass. Now the restoration proper can begin.
In the workshop, the stained glass is thoroughly cleaned using soft sponges soaked in water and Marseille soap, special attention being given to the exterior side.
If the lead came is so badly damaged that it needs to be replaced, a rubbing of the whole design is made. Tracing paper is attached to the surface of the window, then charcoal is rubbed over all the came to obtain a precise copy of the pattern. Where damage is limited to sections, only these areas are traced. These rubbings, together with the photographs documenting the condition of the stained glass window before restoration, are indispensable when reassembling it.
Any broken or missing stained-glass pieces are replaced with glass that has an identical structure and colour. Glass coloured using the grisaille technique is reproduced pictorially by copying the same style as the original.
When the above processes have been completed, the stained glass is ready to be reassembled, with the help of the rubbings produced earlier. Lead came, the same size and shape as those of the original, are then soldered together to hold the pieces of glass in place. Lastly, the design is sealed using traditional putty. When this has set, the restored stained glass window is ready to be returned to its original home.