Both methods ensure smooth, chip-free edges. Better mirror shops go a step further by coating the cut edges with sealant to keep moisture from getting through to the reflective back and eventually tarnishing or oxidizing the mirror. Sealed edges are a must when mirror is installed in a home in a humid climate or along a kitchen backsplash or bath vanity. Mirrors must be bonded to the wall with special mastic. Experienced installers know which mastic to use under what circumstances.
Several factors determine the types of mastic that are used.
Among them is the size of the mirror, whether it is on a wall or ceiling and the type of surface it's being installed over - painted or unpainted drywall, wood, tile or plaster. For safety's sake, manufacturers recommend that all unframed mirrors be installed with at least one type of mastic and a mechanical fastener, such as a decorative molding, J-channel, unobtrusive plastic or metal clips or screws. If plastic fasteners bother you, plan to install decorative light fixtures on the mirror. Or, have the mirror trimmed with wood molding that will hold it in place. With a quality installation and proper care, a mirror will stretch a space and brighten your home - and expand your visual horizons for years to come.