Red Seal Glazier Practice Exam 2025 – Complete Guide for Your Test Prep

The choice of wood as a spacer material in insulated glass is not commonly used primarily due to its physical properties and susceptibility to environmental factors. Spacers are critical components in insulated glass units (IGUs), as they create a separation between the panes of glass and maintain the insulating properties of the unit.

Aluminum, stainless steel, and polymers are all favored materials for spacers because they offer excellent durability, stability, and resistance to moisture and thermal expansion. Aluminum and stainless steel have high strength and low thermal conductivity, which helps maintain the thermal performance of the insulated glass. Additionally, polymers can provide lightweight, flexible, and non-conductive alternatives that also enhance the insulating properties.

In contrast, wood does not perform well under the conditions that insulated glass is typically exposed to. It can absorb moisture, swell, and degrade over time, leading to compromised insulation, increased energy costs, and potential structural failures in the glass unit. Therefore, while wood is used in various construction applications, it is not a practical choice for spacers in insulated glass due to these limitations.