Type the exact width, run and pitch. Get sheets, lengths, screws, ridge, gutter and barge for a skillion or a gable, priced at your rate. Copy it, text it to the supplier or save the PDF. Free, no email.
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Leave at 0 to skip. Use the ex GST rate off your supplier's price list.
14 sheets at 6.26m each
87.7 lineal metres of corrugated for the one face, plus roughly 468 screws.
Pitch factor at 15°: 1.035. Sheet length includes a 0.05m overhang allowance. Laid roof area roughly 66.8m² at ~7 screws per m². Ridge, gutter and barge are the roof's own lengths before laps, so add your lap per join.
Hip roof? Sheets shorten toward the hips, so a straight sheet count over-orders. Take it off a measured plan.
| Profile | Cover | Sheets | Lineal m | Screws |
|---|---|---|---|---|
| Corrugated | 762mm | 14 | 87.7m | ~468 |
| Trimdek-style | 762mm | 14 | 87.7m | ~468 |
| Kliplok-style | 700mm | 15 | 93.9m | ~461 |
Guide only. Real orders come off a measured roof plan with end laps, flashings, penetrations, hips and valleys accounted for, and screw counts follow the manufacturer's fixing pattern for your wind region. Confirm effective cover with your supplier before ordering.
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Measuring the horizontal run off a site plan and ordering sheets at that length is the classic short-order. At 15 degrees the slope is 3.5 percent longer than the plan, at 25 degrees it is 10 percent longer. On a 7m run that is 700mm of missing sheet, and custom-cut lengths cannot be stretched. The truck comes back, the job loses a day, and the margin wears it.
Punch the numbers in while you are still on the roof. The profile table shows how the sheet count moves between corrugated and concealed-fix covers, so you can price both options for the client from the same measure-up.
The sheet runs along the slope, not the horizontal, so you divide the horizontal run from gutter to ridge by the cosine of the pitch. At 15 degrees the factor is about 1.035, so a 6m run needs roughly 6.21m sheets before overhang. At 25 degrees it jumps to about 1.103. This calculator does the trig for you and adds a 0.05m overhang allowance into the gutter.
Effective cover. Corrugated and Trimdek-style both cover about 762mm per sheet once lapped, and concealed-fix Kliplok-style profiles cover around 700mm. On a wide roof that 62mm difference adds up, a 30m gutter line needs 40 corrugated sheets but 43 Kliplok sheets. The comparison table shows all three at your numbers so the difference is not a surprise at ordering time.
The estimate here is roughly 7 screws per square metre of roof, which lands close to the usual pattern of every second crest at battens for corrugated roofs at standard batten spacing. The real number comes from the manufacturer's fixing pattern for your profile, batten spacing and wind region, cyclonic areas fix every crest and need substantially more. Buy the next full box up, nobody has ever regretted spare roofing screws.
Only as a rough upper bound. The maths here assumes every sheet runs full length from gutter to ridge, which is true for a skillion or gable face. On a hip roof the sheets shorten as they approach each hip, so a straight count over-orders lineal metres. Suppliers cut hip roofs from a measured plan for exactly that reason. Use this for the main faces, then get the hip ends detailed properly.
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