Glazing beads are specialized strips used to hold the Insulated Glass Unit (IGU) in the sash.
They can be made of wood, steel, aluminum or vinyl and have a variety of designs for specific windows. Glazing beads can be located on the window's interior or exterior. Some windows use mechanical corners and reglaze with a rubber gasket--or boot glaze--and have no beads
This page will inform you on the types of glazing beads, what can go wrong with them and how to identify them.
Signs of a broken glazing bead
Bead is visibly broken
Glass is not held flush to the sash
Vinyl beads are warped
Wooden beads show signs of rotting
Why do glazing beads break?
Glazing beads often break due to exposure to the elements or mishandling.
Vinyl glazing beads can warp or go brittle from years of sun exposure. Wooden glazing beads can rot from water exposure or insect damage.
Glazing beads can be mishandled by contractors attempting to replace a window's glass. Brittle vinyl beads are fragile and need to be removed with care when re-glazing the sash, otherwise they can crack. Aluminum or steel beads are often bent by contractors working with them. Wood beads can get cracked when they are removed, as they are nailed to the perimeter of the window and need all the nails carefully removed before being reinstalled.
We've seen glazing beads damaged by being improperly reinstalled as well. For beads that use a locking channel, some contractors will miss the channel and try to force the bead in, bending or breaking them in the process. For wood windows, shoddy nailing jobs damage the beads.
Types of glazing beads
Glazing beads vary in material, design and style depending on the type of window, manufacturer and model. Different beads have different ways they lock in to the sash to hold the glass unit. It is best to save your beads and replace them only as a last resort. Some standard glazing beads are shipped in long strips and can be cut to size on site if the beads cannot be saved.
Vinyl glazing beads
Vinyl glazing beads are found in all vinyl windows. They lock into a channel built into the interior of the sash.
Wood glazing beads
Wood glazing beads are found on most wood windows and are nailed to the perimeter of the window that holds the glass.
Aluminum/Steel glazing beads
Aluminum or steel glazing beads lock into a channel built into the glass opening in a window, like vinyl glazing beads do. They are typically found in aluminum or steel windows.
Boot glazes are like a combination of a glazing bead and sealant. They consist of a rubber gasket that surrounds the glass unit and slides into a sash that uses mechanical corners; eliminating the need for silicone sealant to glaze it in. They are typically found in large buildings that have aluminum windows.