GUIDES
Roofing guides
How to get from a tape measure to an order you can defend. Every table in these guides is computed by the same code as the calculators, so the numbers agree with what the tools show.
How to Measure a Roof Without Climbing on It
Footprint, overhang and pitch from the ground and the attic, with a three-section worked example and an error table.
Updated · Uses the roof area calculator and roof pitch calculatorRoof Pitch Explained: Rise per 12, Degrees and the Area Multiplier
What 6:12 means, how to measure it without climbing, and how pitch changes the amount of roofing you need.
Updated · Uses the roof pitch calculator and roof area calculatorGable vs Hip vs Shed Roof: Same Area, Different Materials
Same footprint and pitch means same area. What differs is ridge, hips, edges and waste.
Updated · Uses the roof area calculator and roofing material calculatorRoofing Squares and Shingle Bundles: How to Convert Roof Area
From square feet to squares to bundles, with a bundle table for three packaging sizes.
Updated · Uses the roofing material calculator and roof area calculatorRoof Waste Factor: How Much Extra Roofing to Order
Why waste figures differ so much, and what 5, 10, 15 and 20 percent mean in bundles.
Updated · Uses the roofing material calculator and roof area calculatorUnderlayment, Drip Edge, Starter and Ridge Cap: How Much to Order
The accessory quantities people guess: rolls after laps, drip edge with a 2-inch lap, starter and caps by the lineal foot.
Updated · Uses the roofing material calculatorHow Many Metal Roofing Panels Do I Need?
Panels are ordered by count and cut length, not by area. Here is the arithmetic for both.
Updated · Uses the roof area calculator and roof pitch calculatorRoofing Quote Checklist: What to Prepare Before You Call a Roofer
What to measure and write down first, and the ten things a comparable written quote states.
Updated · Uses the roof area calculator and roofing material calculator