asphalt shingle roof installation

https://wiki-fusion.win/index.php/Understanding_Asphalt_Shingle_Roof_Cost_for_Your_Home

Installing an asphalt shingle roof is a precise process, starting with a clean, dry plywood or OSB deck often covered with an ice and water shield. The roofer snaps chalk lines for alignment, then hand-nails each shingle, staggered for a natural-looking pattern. Cutting around vents and valleys with a utility knife ensures a clean, leak-proof fit.