Calculation of roofing
Enter the house dimensions and pitch angle — we will calculate the slope area and the amount of roofing material accounting for overlaps and waste.
- Horizontal projection area
- 90.7 m² accounting for overhangs
- Slope area
- 104.7 m²
- Material to purchase
- 115.2 m²
The calculation is an estimate. The actual area depends on the roof shape (valleys, dormer windows, chimneys, attic windows) — all of which increase material consumption. A manager will clarify the details when preparing the quote and select the accessory elements (flashings, waterproofing, insulation).
How is it calculated?
Horizontal projection: house length × width + overhangs around the perimeter.
Slope area: projection ÷ cos(angle). For a gable roof — two planes of equal area. For a hip roof, the slope factor is taken approximately; the exact geometry depends on the house's proportions.
Material to purchase: slope area × material factor. Accounts for longitudinal and transverse overlap and offcuts at the ridge and valleys.
An exact calculation depending on the roof shape, the sheet sizes of the specific manufacturer and the presence of additional elements, is made by a manager when preparing the quote.