This collapse occurs when the floor or roof assembly on both sides of a load-bearing center wall collapse, creating a pair of lean-to collapses on opposite sides of the load-bearing wall.

• A. A-frame Collapse
• B. Pancake Collapse
• C. V-Shaped Collapse
• D. Lean-to Collapse

Answer: (A)

When a central load-bearing wall remains while the floor or roof collapses on both sides, the remaining framing on each side tilts toward the center. The two leaning halves form an A-shaped frame around the wall, which is why this pattern is called an A-frame collapse. This differs from a pancake collapse, which falls straight down in a flat layer, a lean-to collapse, which affects only one side, or a V-shaped collapse, where the pieces tilt away from the center to form a V. So the described scenario—the two lean-tos on opposite sides of a central wall forming an A-shaped frame—fits the A-frame collapse.