Removal of Pigmented Structural Glass Panels
Removal of existing glass panels from a wall in order to reapply mastic adhesive that is failing or to replace broken panel is an exacting operation. The mastic used to attach the glass panels to the wall may have become hard and extremely difficult to separate from the ribbed backing of the glass. Fortunately, commercial solvents may be purchased which are capable of softening the hardened mastic such as methyl ethyl ketone, methyl isobutyl ketone, and acetone.
These solvents may be introduced into the cavity behind the glass with a crook-necked polyethylene laboratory squeeze bottle or a large syringe without a needle. (Solvents should be stored in fire-safe metal containers until used and should also be handled with extreme care so that they do not come into contact with the skin.) Such methods make it easy to direct the solvent into the narrow separation between the glass panel and the wall with a minimum of waste and effort. After the mastic has softened, two people using a taut piano wire sawing down from the top can safely and efficiently separate the glass from the wall.
The piano wire/sawing method may be useful in removing the topmost glass panels of a continuous face where no edges occur. The wire can be effectively worked into the joints and will cut through the mastic. With care, a high percentage of the glass panels can be salvaged using this method.