Steps
- Set the scale on the roof plan.
- Use Area to outline each roof plane, or the whole roof if it has one pitch.
- Use Polyline for eaves, rakes, ridges, hips and valleys under separate conditions (drip edge, ridge cap, ice and water shield).
- Measure gutter runs along the eaves for GutterCalc.
Plan area to roof area
Sloped area = plan area × pitch factor (for example about 1.054 for a 4/12 roof and 1.202 for 8/12). RoofMath does the pitch factor, squares and bundles for you. Add 10–15% waste for hips, valleys and starter courses.
Accessories and trim
Keep each linear item in its own condition so the CSV gives you a ready-made order list: drip edge along eaves and rakes, starter strip along eaves, ridge cap along ridges and hips, and ice and water shield along eaves and valleys. Count roof vents, pipe boots and skylights with Count. For ventilation sizing, take the attic floor area to AtticVentCalc.
FAQ
What is a roofing square?
100 square feet of roof surface.
Why does the plan area differ from the roof area?
A plan view is a flat projection; sloped planes are larger than their footprint by the pitch factor.