After a time, lead (which is soft) can start to sag or the cement can become loose and even leak. This will usually be after many years and is often after misuse or support bars not being fitted, and of course the glass gets broken. In any of these cases, it is not the end of your panel. Glass and lead can be replaced and it can be re-cemented. If you have acquired an old panel I can resize it to your requirements

This beautiful original church panel was reconstructed from many broken pieces. In fact not one piece was whole. It hangs from chains inside a landing window and the effect is wow!!!!!