Exterior Calculators

Roofing, siding, and decking cover a house's exterior envelope and its outdoor structure, and share a common approach: the geometry is computed live from your measurements — a pitch multiplier, a gable triangle, a board's width plus its gap — never read off a stored table. What each calculator can't derive, it asks you for directly rather than assuming: waste, bundle or unit coverage, and deck board gap all come from you, because the real number varies by product or manufacturer in ways this site can't verify. Pick the calculator that matches your project below.