Corrugated Metal Gable Roof Calculator
Estimate corrugated metal sheets, screws, and overlaps for roofing projects. Minimizes waste by calculating precise sheet layouts.
About
Installing a metal roof requires strict adherence to overlap standards to prevent leaks and wind uplift. Corrugated sheets function differently than shingles. They require horizontal overlaps (sidelaps) and vertical overlaps (endlaps) if the roof slope exceeds the maximum sheet length. This calculator determines the net coverage per sheet rather than the gross width. It accounts for the ridge cap and fastener density. Errors in this calculation result in either a shortage of expensive custom-cut metal or significant waste from excessive trimming. Fastener counts assume standard spacing for high-wind zones.
Formulas
The number of sheets N depends on the roof length L and the net width of the sheet wnet.
Total area includes the slope factor derived from pitch P.
Reference Data
| Sheet Type | Gross Width | Req. Sidelap | Net Width | Fastener Spacing |
|---|---|---|---|---|
| Standard Corrugated | 26 in | 2 in | 24 in | 24 in O.C. |
| Wide Corrugated | 36 in | 2 in | 34 in | 24 in O.C. |
| R-Panel | 39 in | 3 in | 36 in | 12 in O.C. |
| Standing Seam | 16 in | 0 (Lock) | 16 in | Hidden Clip |
| Endlap (Low Slope) | N/A | 12 in | - | - |
| Endlap (Steep Slope) | N/A | 6 in | - | - |