A roofing system features a plurality of roofing sheets each having an outer perimeter of which two opposing perimeter edges respectively define a fastening edge and a hooking edge. One or more fastening holes penetrate the sheet near the fastening edge. At the hooking edge, the sheet is bent under itself to form a hooking portion reaching back toward the fastening edge. A plurality of hold-downs are placed atop a first row of roofing sheets near the fastening edges thereof, and have apertures aligned with the fastening holes of the roofing sheets, through which the hold-downs are fastened to the a roof deck. The hooking edges of a next row of roofing sheets hook to the affixed hold-downs of the first row, thus coupling the two rows of sheets together and concealing the first row's fastened connection to the roof deck beneath the second row.

A roofing system features a plurality of roofing sheets each having an outer perimeter of which two opposing perimeter edges respectively define a fastening edge and a hooking edge. One or more fastening holes penetrate the sheet near the fastening edge. At the hooking edge, the sheet is bent under itself to form a hooking portion reaching back toward the fastening edge. A plurality of hold-downs are placed atop a first row of roofing sheets near the fastening edges thereof, and have apertures aligned with the fastening holes of the roofing sheets, through which the hold-downs are fastened to the a roof deck. The hooking edges of a next row of roofing sheets hook to the affixed hold-downs of the first row, thus coupling the two rows of sheets together and concealing the first row's fastened connection to the roof deck beneath the second row.

A metal roofing member 1 is disposed side by side with another metal roofing member on a roof base. The metal roofing member 1 has a box-shaped front substrate 10 made of a metal sheet, a rear substrate 11 disposed on the rear side of the front substrate 10, so as to cover an opening of the front substrate 10, and a core material 12 made from a foam resin and filled in between the front substrate 10 and the rear substrate 11. The front substrate 10 results from forming the metal sheet into a box shape. The front substrate 10 has a side wall portion that is continuous in the circumferential direction and is formed by performing drawing or bulging processing on the metal sheet. The front substrate 10 has a height of 4 mm to 8 mm.

A metal roofing member 1 is disposed side by side with another metal roofing member on a roof base. The metal roofing member 1 has a box-shaped front substrate 10 made of a metal sheet, a rear substrate 11 disposed on the rear side of the front substrate 10, so as to cover an opening of the front substrate 10, and a core material 12 made from a foam resin and filled in between the front substrate 10 and the rear substrate 11. The front substrate 10 results from forming the metal sheet into a box shape. The front substrate 10 has a side wall portion that is continuous in the circumferential direction and is formed by performing drawing or bulging processing on the metal sheet. The front substrate 10 has a height of 4 mm to 8 mm.

A body portion 100 of a front substrate 10 includes first side surfaces 105 and second side surfaces 106, each of the second side surfaces 106 being arranged at a position protruding toward the outer side along a width direction 100a than the first side surface 105. Each of the first side surfaces 105 includes a side flange 105a. A protruding width of the side flange 105a from the first side surface 105 is equal to or less than a protruding width of the second side surface 106 from the first side surface 105. A metal roofing member 1 is arranged on a roof base while abutting at least the second side surface 106 against a second side surface of other metal roofing member.

A body portion 100 of a front substrate 10 includes first side surfaces 105 and second side surfaces 106, each of the second side surfaces 106 being arranged at a position protruding toward the outer side along a width direction 100a than the first side surface 105. Each of the first side surfaces 105 includes a side flange 105a. A protruding width of the side flange 105a from the first side surface 105 is equal to or less than a protruding width of the second side surface 106 from the first side surface 105. A metal roofing member 1 is arranged on a roof base while abutting at least the second side surface 106 against a second side surface of other metal roofing member.

A metal roofing material according to the present invention comprises: a front substrate 2 having a body portion 20, the body portion 20 being comprised of a metal sheet and being formed into a box shape; a back substrate disposed on a back side of the front substrate 2 so as to cover an opening of the body portion 20; a core material filled between the body portion 20 and the back substrate, the metal roofing material being arranged side by side on a roof base together with other metal roofing materials, wherein at least one edge indicator 22 in the form of protrusion is provided at an edge portion of a top plate 20a of the body portion 20.

A metal roofing material according to the present invention comprises: a front substrate 2 having a body portion 20, the body portion 20 being comprised of a metal sheet and being formed into a box shape; a back substrate disposed on a back side of the front substrate 2 so as to cover an opening of the body portion 20; a core material filled between the body portion 20 and the back substrate, the metal roofing material being arranged side by side on a roof base together with other metal roofing materials, wherein at least one edge indicator 22 in the form of protrusion is provided at an edge portion of a top plate 20a of the body portion 20.

A lightweight interlocking metal roof system for installation onto a steep or inclined structure roof either directly over the roof decking material or over an existing shingle roofing system, with the metal roofing system installed from the roof ridgeline down to the drip edge of the roof gutter. Cooperating outwardly extending flanges and receiving pockets for capturing and interlocking the metal panels of the roofing system create an interlock between and among panel members with overlying edge ends configured to be resistant to lift up due to winds either across the roof or along the roof edges.

A lightweight interlocking metal roof system for installation onto a steep or inclined structure roof either directly over the roof decking material or over an existing shingle roofing system, with the metal roofing system installed from the roof ridgeline down to the drip edge of the roof gutter. Cooperating outwardly extending flanges and receiving pockets for capturing and interlocking the metal panels of the roofing system create an interlock between and among panel members with overlying edge ends configured to be resistant to lift up due to winds either across the roof or along the roof edges.