Care & Conservation of Stained glass
The term "Stained Glass" describes all types of decorative windows whether they are in a private home or a cathedral. The glass consists of silica (sand), alkali fluxes (potash or soda)and is coloured by the addition of metallic oxides.
Usually the glass is held together within a framework of lead, soldered at each intersection and sealed with a waterproofing compound.
There is no rule about how long a well-made, securely protected window should last without being releaded. It could be for centuries.
Painted windows have glass paint applied, usually to the inside of the panel. The paint is black or brown in colour and it consists of finely crushed glass and iron oxide. When mixed with water the paint can be brushed onto the surface of the glass and then fired in a kiln to fuse it permanently. Over many years the glass paint can become unstable, often due to excess condensation, and the pigments may detach from the glass on which they have been fired.
Cleaning Stained Glass.
Painted windows should not be wet-cleaned on the inside but gently dusted with a soft bristle brush so as not to disturb any loose paintwork.
Non-painted glass can be cleaned using a soft cloth and distilled water.
Protection of Glass. Protecting windows from the elements or vandalism is best accomplished by using black powder-coated, stainless steel wire guards which are made to fit into each individual window opening. Stained glass windows, especially in domestic situations, can be set within double glazed units consisting of two sheets of 4mm toughened glass. This provides good protection and has the added benefit of being easily cleaned.
It is advisable that all stained glass windows are photographically recorded as this will provide an invaluable resource should the window be damaged and need restoring. Take a picture of the whole of the window and then take detailed shots of any special features such as the heads and hands of figures and any lettering/inscriptions. Tips: Use a tripod to provide a steady base and avoid direct sunlight - a bright, cloudy day is best.
Take photos of the damage immediately. Collect even the smallest piece of glass and do not use adhesive tape to hold together broken pieces.
What you can do to help. Regularly inspecting the window(s) is the best thing an owner/guardian can do. Look for any of the situations below and get in touch with your local stained glass expert.
*Loose copper ties
*Loss of glass paint