Our project has corrugated metal roof like which can be shown by clicking the link below.
http://www.sakata-s.co.jp/product/88.html
The roof will be installed almost horizontally as a whole. But the corrugated metal roof has two types of part in itself. One is the horizontal part (top of mountain and bottom of valley) and the other is steep-sloped part. Each part appears repeatedly and shapes stripes. Is it acceptable to apply SRI for low-sloped roof to the first type of roof area (horizontal), and SRI for steep-sloped roof to the latter type of roof area by prorating the total roof area on the basis of two areas according to section drawing?