Roofing system and method

A roofing system, comprising:

• a roof deck able to retain mechanical fasteners;
• the roof deck having peripheral edges and corners;
• roof insulation boards overlaying the roof deck;
• seams formed between the roof insulation boards where the roof insulation boards abut each other;
• a plurality of hold-down straps extending in a first direction, overlaying, and in direct contact with the roof insulation boards;
• the hold down straps being located on the roof insulation boards so that the hold down straps are not overlaying and longitudinally aligned with the seams formed between the roof insulation boards;
• the hold-down straps being spaced from each other in a direction perpendicular to the first direction;
• the hold-down straps having pre-formed mechanical fastener openings therethrough on preselected center to center spacings;
• peripheral edge hold-down straps overlaying and in direct contact with the roof insulation boards extending along each peripheral edge of the roof deck;
• each peripheral edge hold-down strap extending parallel to and being spaced inwardly from an adjacent peripheral edge of the roof deck;
• the peripheral edge hold-down straps having pre-formed mechanical fastener openings therethrough on preselected center to center spacings;
• and
• mechanical fasteners passing down through the mechanical fastener openings in the hold-down straps and the peripheral edge hold-down straps, through the roof insulation boards, and into the roof deck to secure the roof insulation boards to the roof deck.