How far apart are purlins spaced on a panelized roof?

How far apart are purlins spaced on a panelized roof?

• A. 4 feet
• B. 8 feet
• C. 6 feet
• D. 10 feet

Answer: (B)

Panelized roof systems rely on purlins to support long roof panels. The spacing is matched to the panel width so each panel edge sits firmly on a purlin and can be fastened along its length. Many panelized roofs use panels about eight feet wide, so the purlins are placed roughly eight feet apart. This spacing provides solid support for the panel without adding unnecessary framing. A closer spacing, like four feet, adds cost without extra benefit for typical panels, while wider gaps such as six or ten feet can leave panel edges unsupported or misaligned with panel joints.

Panelized roof systems rely on purlins to support long roof panels. The spacing is matched to the panel width so each panel edge sits firmly on a purlin and can be fastened along its length. Many panelized roofs use panels about eight feet wide, so the purlins are placed roughly eight feet apart. This spacing provides solid support for the panel without adding unnecessary framing. A closer spacing, like four feet, adds cost without extra benefit for typical panels, while wider gaps such as six or ten feet can leave panel edges unsupported or misaligned with panel joints.