Based on the general construction module dimensions of multiple times 300 mm (horizontal) the roof overhangs are more easy to adjust. Even when the roof tiles or modules do not have standard dimensions the overhang can just adjust this. In general the beams will cross the outside wall to create the structure for the overhang.
Schematic roof detail with overhang
Almost every module can be used as long as the overhang can be adjusted. For a house with a span of 7200 mm and walls of 400 mm, the total width will be 7800 mm (span is calculated from the middle of the 200 mm bearing wall). With modules of 1400 mm it will be 8400 or 9800 mm width. This results in a large overhang of 9800 – 7800 = 2000 / 2 = 1000 mm or a small overhang of 300 mm (8400 – 7800 = 600 / 3 = 300 mm). The last dimensions are the most likely.
Roof edge detail with overhang. Original detail for the demo house in Mons (B).