A mirror wall is bonded to the wall, not hung on it. Accurate Glass & Mirror, a Bergen County NJ glass shop, flattens and preps the surface, sets each panel in beads of mirror mastic, and adds channel or clips at the bottom so nothing depends on adhesive alone while it cures.
Mirror shows every flaw behind it. A wall that waves by an eighth of an inch will put a slow bend in the reflection, and no adhesive fixes that after the panel is up. So the first hour is prep. High spots get knocked down or skimmed, the surface is cleaned and dried, and a straightedge is run across the wall in both directions before a single panel comes off the cart.
Paint matters too. Solvents still gassing off under a sealed panel can attack the silvering from behind, which is how a new mirror wall grows dark edges in its first year. Bare drywall gets primed and given time to cure. Glossy surfaces get scuffed so the mastic has something to bite. Gym and studio walls get the same treatment over a much larger area, which is exactly where flatness problems show.
Panels are set in beads of mirror mastic, an adhesive made specifically for mirror so it will not attack the backing. The beads run in a pattern that leaves air paths behind the glass rather than sealing the whole back flat, so moisture is never trapped against the silver. The layout is marked on the wall first, then each panel is lifted in, pressed, worked while the adhesive is still open, and held until it grabs. Large panels go up in a set order, because each one has to slide against its neighbor without dragging through fresh mastic on the way.
Adhesive alone is never the plan. J channel or bottom clips carry the actual weight, top clips hold the panel tight to the wall, and the mastic keeps it from shifting between them. Seam positions get decided on paper before anything is cut, because two even panels read better than one wide sheet and a narrow filler strip. Outlets, switches and sconce openings are machined at the Lodi bench and arrive finished, since holes and notches in mirror are cut at the shop, never on a ladder in your house.
Sometimes, if the surface is flat, sound and firmly bonded. Tile with a raised pattern or wide grout joints gives the mastic an uneven bed and telegraphs through the reflection. Loose paneling flexes, which is worse. The safer route is taking the wall back to a flat substrate, or furring and skimming a fresh face for the mirror to sit against.
Slowly, and rarely in one piece. Mastic bonds hard, so panels are usually cut free and taken out in sections with the face of the wall coming along with them. Budget for drywall repair or a skim coat afterward. If the room is likely to change in a few years, cleats and clips without full adhesive coverage are worth raising at the measure.
Every panel is cut and edged in the Lodi shop to numbers taken in your room, sconce holes and all. Book the free in-home measure, tell us what is going on that wall, and the seams get laid out before anything is scored.
