Roofing Takeoff

Hips, valleys, dormers and multi-pitch roofs are quantified from digital plans to produce squares, ridge, hip, valley and eave linear footage, plus underlayment, flashing and accessory quantities.

How we take it off

Roof area is measured from the plan and adjusted per actual pitch on each plane — a 6:12 and a 12:12 section of the same footprint area are very different material quantities, and treating the whole roof as one average pitch is the single most common error we catch. Ridge, hip and valley lines are measured along their true (sloped) length, not their plan-view projection. Accessories — vents, drip edge, ice and water shield at eaves and valleys — are counted per the roof plan and local code minimums shown in the details.

What the second-estimator review is checking

• Entire roof priced at one average pitch instead of pitch-adjusted per plane
• Hip and valley lengths measured in plan view instead of true sloped length
• Ice and water shield coverage at eaves and valleys left off in climates that require it
• Waste factor not adjusted for complex geometry — a simple gable and a roof with a dozen hips and valleys do not waste material at the same rate