Can I Repair My Own Double Pane Windows?

About Double Pane Windows

• Double pane windows hold two pieces of glass close together with a ½ to ¾ inch cushion of air or gas between them. This layer of air or argon gas acts as an insulator to prevent the transfer of heat from one side of the window to the other. The frames that hold the glass must also be more sophisticated, and wood, vinyl or vinyl-clad wood function better than metal frames for these windows. Often low-E, that is low emissive, coatings increase the energy savings for double pane windows. These microscopically-thin coatings made from metal oxides help to block the flow of heat both into and out of the window.

Condensation in Double Pane Windows

• The accumulation of liquid water on a relatively cold surface is called condensation. This water can occur between the panes of double pane windows. It may or may not be visible, according to the National Association of Certified Building Inspectors. Moisture from condensation tends to carve out the same paths of water flow and can carve grooves in the glass surface. If silica gel is used inside the window to absorb the water from condensation, it can become saturated and create white “snowflakes” that indicate failure of the window’s heat blocking ability. To solve this problem, you must replace the glass in the window.

Cracked Double Pane Windows

• To repair a cracked window, you must open the frame with a screwdriver and separate the two pieces of glass, being careful not to damage the unbroken pane. Remove the butyl sealant from the edge of the frame. The sealant is a black, rubber-like material. Clean the new glass and the old pane with a solution of isopropyl alcohol, vinegar and water to remove all dirt and grease so that you can apply a silicone sealer to clean surfaces. Insert a new piece of glass to replace the damaged pane using the spacers that keep the two panes separated. Apply the silicone sealer first to the perimeter of the spacer, and then another coating of silicone in a thick bead to cover the spacer. Allow the silicone to cure for 24 hours before placing the window back into the frame.

Precautions When Repairing Double Paned Windows

• When repairing double pane windows, take care not to damage the butyl seal material. This material should be re-used when replacing the new pane into the window. Similarly, when working with double panes, place the window on a blanket or soft surface to avoid damaging the unbroken pane of the unit.