What are insulated spacers?

• A. Window spacers made of metal
• B. Spacers between panes made of glass
• C. Window spacers made of insulating materials (foam, plastic or glass)
• D. Window spacers are not used in insulated glazing

Answer: (C)

Insulated spacers are the edge members in an insulated glazing unit that keep the panes apart and seal the unit, and they are made from insulating materials such as foam, plastic, or glass. This insulating material reduces heat transfer at the window edge (thermal bridging), which improves the window’s overall energy performance and helps prevent condensation along the edges. Metal spacers conduct heat and would not be considered insulated spacers, while a spacer made of glass would still transfer more heat than the insulating materials, so it isn’t identified as insulated spacers. Spacers are essential in insulated glazing, so saying they aren’t used is incorrect.