Roof area, squares, and shingle bundles from your footprint and pitch — plus the rest of the materials.
Measure the building footprint at ground level, not the slope.
4/12 to 6/12 covers most houses. Not sure? See the pitch table below.
Based on the dimensions on the left — edit them to match your roof and this updates as you type.
Harness, rope grab, and a ridge anchor — the whole setup, before any material goes up
Tip: Falls are the leading cause of death in roofing. Anything above a single storey or a 6/12 pitch needs this and roof jacks.
42 bundles = 14 squares at 3 bundles per square
Tip: Buy all bundles in one order. Colour lots vary between batches and a mid-roof switch shows.
Goes down before the shingles, over the whole deck
Tip: Synthetic beats felt on a hot roof — it won't wrinkle or tear underfoot.
136 ft of perimeter
Tip: Drip edge goes under the underlayment at the rakes, over it at the eaves.
80 ft of eaves
Tip: Don't substitute cut-up shingles. Starter strip has the sealant in the right place.
40 ft of ridge at ~20 ft per bundle
~4500 nails at 4 per shingle
Tip: Check your local code — high-wind zones often require 6 nails per shingle, not 4.
Hand-nailing a full roof is a two-day job that a nailer does in hours
Before you start
Re-roofing usually needs a permit, and most codes allow only two layers of shingles before a full tear-off. Check with your local building department first. Anything above a 6/12 pitch or a single storey warrants roof jacks and a harness — falls are the leading cause of death in roofing.
A roof is always bigger than the footprint it sits on. Multiply your footprint area by the number for your pitch to get the actual roof area.
| Pitch | Multiplier | Angle | 1,000 sq ft footprint becomes |
|---|---|---|---|
| 2/12 | 1.014 | 9.5° | 1,014 sq ft |
| 3/12 | 1.031 | 14.0° | 1,031 sq ft |
| 4/12 | 1.054 | 18.4° | 1,054 sq ft |
| 5/12 | 1.083 | 22.6° | 1,083 sq ft |
| 6/12 | 1.118 | 26.6° | 1,118 sq ft |
| 7/12 | 1.158 | 30.3° | 1,158 sq ft |
| 8/12 | 1.202 | 33.7° | 1,202 sq ft |
| 9/12 | 1.250 | 36.9° | 1,250 sq ft |
| 10/12 | 1.302 | 39.8° | 1,302 sq ft |
| 11/12 | 1.357 | 42.5° | 1,357 sq ft |
| 12/12 | 1.414 | 45.0° | 1,414 sq ft |
How to measure your pitch: hold a level horizontally against the roof line, mark 12 inches along it, then measure straight down from that mark to the roof surface. That drop in inches is your rise — a 6 inch drop is a 6/12 pitch.