How to Repair the Edges of a Mirror

Kelly Gray

As mirrors age, the edges begin to deteriorate due to moisture and contaminants in the air. The silver nitrate that forms the reflective coating of the mirror begins to loosen and black edges occur in the corners of the mirror.

A old mirror can look new again by adding a wooden frame.

Though there is no way to add more silver nitrate to the damaged mirror, you can freshen up your mirror by creating an eye-catching frame to cover the edges.

  1. Select wood molding for the new mirror frame. Woods come in a variety of types such as oak, pine, redwood and cherry. Different colors also are available, such as red, mahogany, black and shades of brown. The color and type of wood you choose will depend on your room's decor.

  2. Measure the current mirror frame. Determine the length of the mirror, and decide how wide the molding needs to be to cover the edge and any imperfections in the mirror.

  3. Cut the molding to length using a hand saw. Measure the molding twice before cutting to ensure the measurements are correct.

  4. Mark the cut molding in the places where the wall brackets hold the mirror. Cut the bracket spaces out using a saw. Use a chisel for finer cuts.

  5. Sand the pieces of molding before adding varnish. Varnish is not required; however, it does help make each piece somewhat water resistant.

  6. Attach the molding to the exterior of the mirror by applying a thin line of marine glue to the back of the molding. Marine glue is an adhesive used for wood and other construction projects. Press the molding into the correct position, covering any deteriorated edges.


Adding additional coats of varnish will make the molding shinier. If adding additional coats, sand in- between each varnish application. Hold the piece of molding for at least 10 minutes or until the glue has set. Install the bottom piece of the frame first, so that the left and right pieces can rest on it.

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