In light weight panelized roof configurations, Beams are spaced how far apart?

• A. Beams: 16'-32' Apart
• B. Beams: 6'-20' Apart
• C. Beams: 12'-40' Apart
• D. Beams: 8' Apart

Answer: (C)

In lightweight panelized roof systems, the deck is carried by a few long-span beams, with large panels bridging the gaps between them. This design uses wide spacing to maximize the unobstructed roof area you can work from during ventilation and to simplify the supporting framework without cluttering the roof with lots of members. The typical range for beam spacing in these configurations is fairly broad, about 12 feet to 40 feet apart. That range reflects the need to support large, lightweight panels while still providing enough structural continuity. Spacing much tighter (like 6 to 20 feet) would mean more beams and more obstructions, making ventilation openings harder to create and work around; spacing much wider than 40 feet could compromise structural behavior under fire. So the 12 to 40 feet range best matches how panelized roofs are usually built and how crews need to operate on them.