A 24×24 ft gable roof at 4/12 with 12-in overhangs needs 18 panels of 36-in coverage (9 per side), each 13' 9" long, plus about 571 screws.
| Item | Length | Buy |
|---|---|---|
| Ridge cap | 26 ft | 3 × 10½ ft |
| Eave trim | 52 ft | 6 × 10½ ft |
| Rake trim | 55 ft | 6 × 10½ ft |
| Inside closures (eave) | 52 ft | 18 × 36 in |
| Outside closures (ridge) | 52 ft | 18 × 36 in |
| Profile | Panels | Lin ft | Panel cost |
|---|---|---|---|
| 36-in rib panel36-in coverage | 18 | 248 | $1,008 |
| 5V crimp24-in coverage | 26 | 358 | $1,222 |
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 | 13' 5" | 18 | 697 | 558 | $1,008 |
| 4/12 | 13' 9" | 18 | 713 | 571 | $1,008 |
| 5/12 | 14' 1" | 18 | 732 | 586 | $1,098 |
| 6/12 | 14' 7" | 18 | 756 | 605 | $1,098 |
| 8/12 | 15' 8" | 18 | 812 | 650 | $1,098 |
Roof area: 26 × 26 ft of plan × 1.054 = 713 sq ft (7.1 squares). At Fabral's 80 screws per square that's 571 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.