How it works
Estimate total sloped area of a symmetrical gable roof from building length, total span and rise.
Core method:
Half-run = span/2. Slope length = √(half-run² + rise²). Two-slope roof area = 2 × building length × slope length.
Half-run = span/2. Slope length = √(half-run² + rise²). Two-slope roof area = 2 × building length × slope length.
Before you use the result: Check project drawings, supplier data and site conditions before ordering materials.