Frequently Asked Questions

Calculator Accuracy, Waste Factors & Usage

This FAQ answers the most common questions about Smart Roofing Calculator. Topics include calculator accuracy (typically within 5-7% of professional takeoffs), why pitch matters for every estimate (it affects total surface area), how to choose the right waste factor for your roof type, what slope multiplier means, why our nail count assumes 4 nails per shingle (6 in high-wind zones), and how to combine multiple calculators for a full materials list. Use this page as your quick reference.