A 30×50 ft gable roof at 4/12 with 12-in overhangs needs 36 panels of 36-in coverage (18 per side), each 16' 11" long, plus about 1,404 screws.
| Item | Length | Buy |
|---|---|---|
| Ridge cap | 52 ft | 6 × 10½ ft |
| Eave trim | 104 ft | 11 × 10½ ft |
| Rake trim | 68 ft | 7 × 10½ ft |
| Inside closures (eave) | 104 ft | 35 × 36 in |
| Outside closures (ridge) | 104 ft | 35 × 36 in |
| Profile | Panels | Lin ft | Panel cost |
|---|---|---|---|
| 36-in rib panel36-in coverage | 36 | 609 | $2,466 |
| 5V crimp24-in coverage | 52 | 880 | $2,964 |
29 ga Galvalume prices from McCoy's (San Marcos, TX), Oct 23, 2026; cut-to-length uses the same per-foot rate. Eave and rake trim vary by supplier — get a quote with the panels.
| Pitch | Panel length | Panels | Roof sq ft | Screws | Panel cost |
|---|---|---|---|---|---|
| 3/12 | 16' 6" | 36 | 1,715 | 1,373 | $2,406 |
| 4/12 | 16' 11" | 36 | 1,754 | 1,404 | $2,466 |
| 5/12 | 17' 4" | 36 | 1,803 | 1,443 | $2,527 |
| 6/12 | 17' 11" | 36 | 1,860 | 1,489 | $2,612 |
| 8/12 | 19' 3" | 36 | 2,000 | 1,600 | $2,807 |
Roof area: 52 × 32 ft of plan × 1.054 = 1,754 sq ft (17.5 squares). At Fabral's 80 screws per square that's 1,404 panel screws — #14 × 1 in Woodtite into a plywood or OSB deck, #10 × 1½ in into purlins — before trim and stitch screws.
Under 3/12 the IRC requires lap sealant on exposed-fastener panels; 36-in rib panels are rated down to 2½/12 by their makers and 5V crimp to 3/12. At 4/12 either profile is fine without sealant.
The full method, material data and tips are on the main metal roofing calculator page.