Double glazing a stained glass window refers to the act of encapsulating the decorative stained glass in between two panels of glass. This not only protects the stained glass, but helps keep your home safe from intruders and improves the heat and sound insulation in your home. Double glazing a stained glass window requires knowledge of windows and window installation. Many people choose to use professionals for this job, as it is not an easy do-it-yourself project.
Select and purchase two vented windows which will be installed on either side of your stained glass. These windows should be single-pane, and at least 4mm thick. Glass less than 4mm thick may not provide the insulation benefits of double glazing.
Apply caulking or silicone where the window will be installed, including to the exterior casings, if possible. Apply two beads of caulking along the outside sill.
Put the bottom of the window into place, and carefully tip the top back until it slips into the frame. Use the tape measure and level to check that it is level and square both horizontally and vertically.
Drill one 2-inch screw into each side to hold the window in place. Place this screw into the upper side jamb, through to the framing.
Apply a bead of caulking or silicone around the entire window. While it is more expensive, it is wise to use silicone on at least the top of the window. Silicone is more durable, and prevents water leaks better than acrylic caulking.
Repeat the process to install a second window on the inside of the stained glass.
It is very important to select vented windows for this project. Otherwise, condensation can collect between the windows and damage the stained glass.