Back home, she examined the window. On the interior side, she found thin vinyl or aluminum strips holding the glass in place—the glazing beads. She slid a stiff putty knife into the seam and gently pried. Snap! The first bead broke. She learned the hard way: start at the middle of the longest side, not the corner. The second bead came off cleanly. She labeled each piece (Top, Bottom, Left, Right) with masking tape.
Home again, she set the new IGU into the frame without sealant first. It slid in perfectly. She then inserted the plastic shims (bought for $3) at the bottom corners to lift the glass evenly. This prevents pressure points that cause future cracks. how to replace a double pane window glass
She brought the broken IGU to the glass shop. The tech measured it with a caliper. “This is 5/8 inch thick,” he said. “The measurement you wrote down was 3/4 inch. It wouldn’t have fit.” Sarah gulped. He cut a new unit to the exact thickness and size in 20 minutes. Lesson learned: Let the pros measure or confirm your numbers. Back home, she examined the window