Insulated panel roof sheets - Bondor, Versiclad and Apollo, are all designed to overhang the edge beams to accommodate specialised flashings required

When the roof sheet is selected to be an Insulated Panel, the minimum overhangs are added automatically

These overhangs add to the overall dimensions already set in the Shapes and Dimensions properties

The overall width (LHS dimension) = Frame Width + Front and Back Overhangs + Gutter

The overall length (Bottom dimension) = Frame Length + Left and Right Overhangs

To maintain the correct overall dimensions for the structure, you can choose to edit the 'OVERALL' dimensions, which take the overhangs into account by selecting the dimension at the bottom or on the left