What holds multiple layers of polystyrene board together?

• A. Wood glue
• B. Nails
• C. Staples
• D. Wood skewers

Answer: (D)

Holding multiple layers of polystyrene board together relies on a simple mechanical fastener that passes through all layers to keep them aligned. Wooden skewers act like dowels, providing a straight, thin pin that can be driven through the stack. This pins the boards together with minimal compression, and you can trim the ends flush for a neat finish. Glue can cause the foam to swell, dissolve, or leave uneven bonds, and nails or staples tend to crush the foam and create dents or gaps. The skewers give a stable, reversible connection that supports the stacked panels without damaging the material.