How do I measure my roof for shingles?

Measure the length and width of each roof plane (flat section). Multiply to get square footage, then add all planes together. For pitched roofs, use a pitch multiplier or measure along the roof surface. One roofing square = 100 square feet.

How much extra roofing material should I buy?

Add 10% for simple gable roofs with minimal waste. Add 15-20% for complex roofs with valleys, dormers, and hips. This covers waste from cuts, starter strips, ridge caps, and a few extra bundles for future repairs.

How many shingle bundles are in a square?

Typically 3 bundles equal one square (100 sq ft) for standard 3-tab shingles. Architectural shingles may be 4 bundles per square. Always check the bundle coverage listed by the manufacturer.

What other materials do I need besides shingles?

You need underlayment (felt or synthetic), drip edge, ice and water shield (valleys and eaves), ridge cap shingles, roofing nails, and flashing. Don't forget ventilation components if replacing or upgrading.

How long do different roofing materials last?

Asphalt shingles: 15-30 years, Architectural shingles: 25-50 years, Metal roofing: 40-70 years, Tile: 50-100 years, Slate: 100+ years. Lifespan depends on quality, installation, climate, and maintenance.

Everyday

Roofing Calculator

Calculate roof area, squares, and shingle bundles needed.

House Base Area (sq ft)Length × Width of the building footprint

Roof Pitch

Waste %

Enter base area

How to Use This Calculator

Measure Roof Dimensions

Measure length and width of each roof section from edge to edge. For safety, measure from ground using roof pitch and building dimensions, or hire a professional to measure.

Account for Roof Pitch

Identify your roof pitch (rise over run, e.g., 6/12). Apply the appropriate pitch multiplier to your measurements since pitched roofs have more surface area than flat measurements suggest.

Calculate Roofing Squares

Enter dimensions and pitch. The calculator converts to roofing squares (100 sq ft each). It accounts for waste and complexity factors.

Determine Bundle Count

Convert squares to bundles (typically 3 per square). Add extra for starter strips, ridge caps, and waste. Order complete materials including underlayment and flashing. Consider hiring professionals for safety.