Roofing Shingle Calculator

Determine roofing squares, architectural shingle bundle counts, starter strips, and ridge caps including complexity waste factors.

Base Ground Footprint (Square Feet) Total building ground area including 1-2 ft overhangs

Roof Pitch

Roof Complexity / Waste

Ridge & Hip Length (Linear Ft) For ridge cap shingles (~33 LF/bundle)

Eave Perimeter (Linear Ft) For starter strip shingles (~105 LF/bundle)

Field Shingles to Order

85 Bundles

28.3 Squares (3 bundles per square)

Ridge Cap Bundles 3 Bundles @ ~33 linear ft / bundle

Starter Strip Bundles 2 Bundles @ ~105 linear ft / bundle

What is a Roofing Square? One "Square" equals 100 square feet of finished roof surface area. Standard architectural laminated shingles are packaged at 3 bundles per square (weighing ~70 to 80 lbs per bundle).

How Roofing Squares and Bundles Are Calculated

Roof surface area exceeds flat ground footprint due to the pitch angle:

True Area = Ground Footprint × Pitch Factor
Total Squares = (True Area × Waste Factor) / 100
Field Bundles = Total Squares × 3 bundles/square

Valley cuts and diagonal hip cuts consume significant shingle material, necessitating a minimum 15% waste allowance on hip roofs compared to 10% on simple gables.

Frequently Asked Questions

How many bundles of shingles make 1 square?

Standard architectural/dimensional shingles require 3 bundles per square (33.3 sq ft per bundle). Heavy luxury shingles may require 4 or 5 bundles per square.

How many nails are used per shingle?

Standard installation requires 4 roofing nails per shingle. In high-wind zones (110+ MPH), manufacturers require 6 nails per shingle driven into the designated double-ply nail zone.

How many rolls of synthetic underlayment do I need?

One standard roll of synthetic roof underlayment covers 10 squares (1,000 sq ft) accounting for 4-inch side laps and 6-inch end laps.