Once the footprint including overhang areas have been determined for each area, find the appropriate slope or pitch factor in the chart below. Note the area of 77ft2 that needs to be subtracted for the recessed area. Multiply L x W to calculate the area for each rectangular section. In Figure 4 below, the dashed blue lines give a simplified view of the footprint. Start by finding the footprint area and multiply by the correct slope factor determined by pitch. Keep in mind that an experienced metal roofing contractor will need to factor in extended labour time for areas of your roof that will require precision metalworking skills. Multiple adjacent pitches, dormers, and turrets are common. Most roofs in Canada would be considered on the complex side.
Calculate roof / tile surface in ArchiCAD
