What to Expect When Installing Mirrors & Glass Railings

Everything begins with a field measurement to the finished surface — the actual wall for a mirror, the actual stair run or deck edge for a railing — never a drawing or a rough opening. For a mirror, the glazier records dimensions and the location of any sconces or outlets to cut around. For a railing, the visit goes further: confirming the structure behind the finish and specifying a system that meets the code load and deflection limits. That engineering step is what separates a railing that passes inspection from one that does not.

Measurements go to the shop, where mirror glass is cut and its edges flat-polished or beveled, or where tempered and laminated railing panels are cut with their holes and notches bored. As with all custom glass, tempered panels cannot be trimmed after heat-treating, so accuracy at the shop is everything. Plan on roughly one to three weeks from measurement to install while the glass is fabricated and any special edge work or cutouts are completed.

On install day the two products diverge. A mirror is set on mastic and backed up with mechanical clips so it seats flush and stays put, then checked for even reveals against the wall. A railing has its standoffs, base shoe, or posts anchored into framing or the structural deck first, then the glass panels are set, leveled, and locked in. The crew finishes a railing by push-testing it for rigidity, confirming it does not flex beyond the allowable limit before they leave.