How to Make a Double Pane Window

Gently place the window on a firm surface, interior side up. Choose a surface that is not easily damaged, or not precious to you in case the glass breaks. Use the putty knife to scrape the glazing off the interior of the window pane. Do not damage the glass itself. Clean the glass with glass cleaner and wipe with a clean cloth. Allow the window to air dry before proceeding, approximately 15 minutes.

Trim the plastic edging that holds the glass in place, so it is even with the pane of glass. When finished, the plastic edging should be flush with the glass. Use the putty knife to scrape off any edging stuck to the window frame or glass.

Carefully measure the top and bottom of the interior of the window. Cut two pieces of plastic edging, one for the top of the window, the other for the bottom.

Put on the rubber gloves. Apply the adhesive directly to the window pane. You should have one strip of adhesive at the top of the glass, another at the bottom. The adhesive should cover all the edging at the top and bottom, and a small amount of the glass. Don't worry getting too much on the window. You will wipe away the excess in a moment.

With the U-channel of the edging facing toward the center of the window pane, press the two strips you cut in Step 3 firmly into place along the top and bottom of the window. Apply pressure to ensure that everything bonds together. Notice that some of the adhesive squeezes out around the edging. Wipe this away with your rag.

Cut two more strips of edging, one for either side of the window pane. Secure these in place with the adhesive, with the U-channel facing toward the center of the window pane. Press firmly into place and wipe away the excess adhesive with the rag. Allow the adhesive to dry according to the manufacturer's directions. Do not proceed until the adhesive is completely dry.

Find the gaps between the edging in the corners of the window pane. Apply adhesive in these spots to seal the edging, even if the gap appears very small. This is important to the stability of the finished window. You don't need very much adhesive for this, so wipe away any excess with a rag.

Pull the edging away from the window frame slightly, and apply enough adhesive to secure the edging to the window frame. Press the edging back into place and wipe away any excess adhesive. Allow the adhesive to dry according to the manufacturer's directions.

Use glass cleaner to clean the new pane of glass. Wipe clean with the cloth and allow to air dry, approximately 15 minutes. Run a bead of adhesive around the edging you previously installed, and press the new pane of glass into place. Apply pressure to ensure everything bonds, but be careful not to break the glass.

Install glazier's points around the edge of the glass according to the manufacturer's directions. Do not skip this step. Allow the adhesive to dry and cure according to the manufacturer's directions. As a general rule, set the window aside and allow to dry for 24 to 36 hours, though this may vary depending on the exact adhesive used.

Apply a very small amount of window glazing to the new pane of glass. Use a clean rag to spread this around the glass. Do not apply too much glazing and wipe away any excess glazing with a rag. Allow this glazing to dry and cure, according to the manufacturer's directions, in a room with low humidity. When the glaze is cured, the window frame can be painted, if you like, or installed immediately.