How many bundles of shingles per square?

Standard 3-tab shingles come 3 bundles per square (100 sq ft). Architectural/dimensional shingles typically require 3–4 bundles per square depending on brand.

What is a roofing square?

One roofing square equals 100 square feet of roof surface. It is the standard unit used to measure and price roofing materials.

How much waste should I add for shingles?

Add 10% waste for simple gable roofs, 12–15% for complex hipped or cut-up roofs with multiple valleys and hips.

How does roof pitch affect shingle quantity?

Steeper pitches increase the actual surface area vs. the footprint. A 9/12 pitch multiplies area by ~1.36, requiring significantly more materials than a flat or low-slope roof.

What is the difference between 3-tab and architectural shingles?

3-tab shingles are flat and uniform, lasting 20–25 years. Architectural (dimensional) shingles are thicker and layered, lasting 25–30+ years, and are now the most common type installed.

Shingle Calculator

Calculate how many asphalt shingle bundles you need for your roof. Enter roof area, pitch, and waste percentage to get 3-tab and architectural shingle bundle counts.

Roof Area (sq ft)

sq ft

Roof Pitch

Waste %

Roofing Squares

—

Bundles Needed (3-tab) —

Bundles (Architectural) —

Extended More scenarios, charts & detailed breakdown ▾

Roof Area (sq ft)

sq ft

Pitch Factor

Waste %

Squares

—

Bundles (3/sq) —

Professional Full parameters & maximum detail ▾

Roof Area (sq ft)

sq ft

Pitch Factor

Waste %

Ridge Linear Feet

Hip/Valley Linear Feet

Eave Length for Ice Shield (ft)

Tear-Off Required?

Materials

Adjusted Squares —

Shingle Bundles —

Starter Strip (lin ft) —

Ridge Cap Bundles —

Accessories

Drip Edge (lin ft) —

Ice & Water Shield (sq ft) —

Nails Needed (approx) —

Tear-Off Note —

How to Use This Calculator

Enter your roof area in square feet (length × width × number of slopes).
Select your pitch category — low, medium, or high.
Set waste % (10% for simple roofs, 15% for complex).
Results show roofing squares and bundles for both 3-tab and architectural shingles.

Formula

Adjusted Area = Roof Area × Pitch Factor × (1 + Waste%)

Squares = Adjusted Area ÷ 100

Bundles = Squares × 3 (3-tab) or Squares × 3.5 (architectural)

Example

Example: 1,500 sq ft roof, medium pitch, 10% waste → 1,500 × 1.18 × 1.10 = 1,947 sq ft adjusted → 19.5 squares → 59 bundles of 3-tab shingles.

Frequently Asked Questions

Standard 3-tab shingles come 3 bundles per square (100 sq ft). Architectural/dimensional shingles typically require 3–4 bundles per square depending on brand.
One roofing square equals 100 square feet of roof surface. It is the standard unit used to measure and price roofing materials.
Add 10% waste for simple gable roofs, 12–15% for complex hipped or cut-up roofs with multiple valleys and hips.
Steeper pitches increase the actual surface area vs. the footprint. A 9/12 pitch multiplies area by ~1.36, requiring significantly more materials than a flat or low-slope roof.
3-tab shingles are flat and uniform, lasting 20–25 years. Architectural (dimensional) shingles are thicker and layered, lasting 25–30+ years, and are now the most common type installed.

Related Calculators

Sources & References (5) ▾

GAF Shingle Installation Guide — GAF
CertainTeed Shingle Installation Manual — CertainTeed
Owens Corning Roofing Resources — Owens Corning
IRC Chapter 9 – Roof Assemblies — ICC / IRC
NRCA Roofing Manual — National Roofing Contractors Association