Moveable transoms are their own technical condition. Their clearances depend on whether the transom is installed wall-to-wall, glass-to-glass or wall-to-glass, and on whether clamps or hinges are used.

What changes the calculation

• Clamp family versus hinge family
• Maximum published transom width and height
• Whether both sides of the transom meet walls, fixed panels, or one of each
• The cutout template required by the selected transom hardware

Recommendation

Treat the transom as a dedicated system and size it from the current hardware template. Do not assume that generic fixed-panel clearances automatically apply to transom hardware.