Window panes are held in place in vinyl windows through a combination of tape and vinyl snap bead trim. The tape or other adhesive is between the glass and the back part of the window frame with the snap bead over the front of the glass securing the glass in place. Replacing vinyl snap bead trim on window frames because of discoloration or cracking is a relatively simple process. Replacement snap bead is available through the manufacturer of your window.
Analyze the snap bead and determine which ones overlap. Side snap beads overlap the upper and lower snap beads. The snap beads that overlap must come off first.
Insert the blade of a rigid putty knife in the seam between the vinyl snap bead and window frame at one end of the snap bead. Twist the handle of the putty knife to pry the front of the snap bead away from the frame.
Slide the putty knife down the length of the snap bead to remove the piece completely away from the window frame. Repeat the process for the opposite side and the bottom snap bead.
Pry the upper snap bead away from the window while a friend holds the glass of the window. This prevents the glass from simply falling out of the window when you release the last vinyl snap bead.
Measure the top of the window frame with a tape measure and transfer the measurement to the replacement vinyl snap bead. Cut the snap bead to size with tin snips. Tin snips cut through the snap bead quickly.
Place the back of the snap bead over the glass and press the channel of the snap bead into the channel of the upper window frame with your thumbs. Repeat the measuring and installation process for the lower snap bead.
Measure between the upper and lower snap beads on each side. Transfer the measurements to the side pieces of replacement vinyl snap bead. Press them into place on the window frame with your thumbs.