Squares to square feet calculator
Convert roofing squares and square feet both ways. One square = 100 ft²—pure unit math.
Convert roofing squares and square feet
One roofing square = 100 ft². This tool only converts units—no bundles or pitch.
Conversion result
Enter a value and click Convert units.
How to Calculate Squares To Square Feet Calculator Manually
Step 1: Start with Verified Roof Dimensions
Measure ridge length, eave length, and the horizontal run from ridge to eave on each plane. Never use floor plan area as a proxy for roof surface—they differ by the slope factor and overhang.
Step 2: Apply the Slope Factor to Each Plane
For each rectangular roof section: sloped area = (ridge/eave length) × horizontal depth × slope factor. Slope factor for 6/12 = 1.118; for 8/12 = 1.202; for 12/12 = 1.414.
Step 3: Sum All Planes and Convert to Squares
Add sloped areas from every facet. Divide total ft² by 100 to get roofing squares. A 2,400 ft² sloped roof = 24 squares. This is the number contractors use to price labor and materials.
Step 4: Add Waste Before Converting to Product Units
Simple gable roofs: 5–8% waste. Hip or cut-up roofs: 10–15%. Multiply sloped ft² by (1 + waste%) then divide by coverage per bundle, roll, or panel to get order quantities.
Step 5: Double-Check Against Field Measure Before Ordering
Planning tools give planning numbers. Walk the roof or use a trusted aerial measurement before submitting a material order. A 5% error on a 30-square job = 1.5 squares of material waste.
Squares To Square Feet Calculator Formulas
- Slope factor = √(1 + (rise ÷ run)²) [e.g. 6/12 pitch: √(1 + 0.25) = 1.118]
- Sloped area = Plan footprint ft² × Slope factor
- Order quantity = ceil(Sloped area × (1 + Waste %) ÷ Unit coverage) [bundles, rolls, or panels]
Use this as a planning starting point. Complex roofs with mixed pitches, dormers, or stepped outlines need individual plane-by-plane takeoffs for accurate ordering.
Squares and square feet on real roofing jobs
Why 100 ft² per square exists
Roofing squares bundle large areas into a single trade unit so crews and distributors can quote faster than quoting raw ft² alone.
Bid review without calculator mistakes
When one line shows squares and another shows ft², convert before you compare dollars per unit—otherwise you misread value by 100×.
Frequently Asked Questions — Squares to Square Feet Calculator
Unit conversion only—bundles use separate tools.
How many square feet are in a roofing square?+
One roofing square equals 100 ft² of roof surface. For better estimating accuracy, cross-check material pricing, labor rates, and waste contingency with your project notes, then confirm scope validation before final ordering. This keeps your final estimate aligned with real site conditions and reduces costly quantity revisions. Recheck dimensions, product coverage, and install requirements before purchase.
How do I convert squares to ft²?+
Multiply squares by 100. Example: 18.2 squares → 1,820 ft². For better estimating accuracy, cross-check material pricing, labor rates, and waste contingency with your project notes, then confirm scope validation before final ordering. This keeps your final estimate aligned with real site conditions and reduces costly quantity revisions. Recheck dimensions, product coverage, and install requirements before purchase.
How do I convert roof ft² to squares?+
Divide roof surface ft² by 100. Example: 2,450 ft² → 24.5 squares. For better estimating accuracy, cross-check material pricing, labor rates, and waste contingency with your project notes, then confirm scope validation before final ordering. This keeps your final estimate aligned with real site conditions and reduces costly quantity revisions.
Is this the same as bundle coverage?+
No. Bundle coverage is ft² per bundle from the manufacturer. Squares only convert 100 ft² units. For better estimating accuracy, cross-check material pricing, labor rates, and waste contingency with your project notes, then confirm scope validation before final ordering. This keeps your final estimate aligned with real site conditions and reduces costly quantity revisions.
Why do quotes mix squares and ft²?+
Trades use squares; some suppliers quote in ft². Converting keeps you aligned with both. For better estimating accuracy, cross-check material pricing, labor rates, and waste contingency with your project notes, then confirm scope validation before final ordering. This keeps your final estimate aligned with real site conditions and reduces costly quantity revisions.
Does this tool include pitch?+
No. Enter the roof surface area or squares you already trust from a takeoff or calculator. For better estimating accuracy, cross-check material pricing, labor rates, and waste contingency with your project notes, then confirm scope validation before final ordering. This keeps your final estimate aligned with real site conditions and reduces costly quantity revisions.
What about metric?+
Results show m² as a reference from the same roof ft². For better estimating accuracy, cross-check material pricing, labor rates, and waste contingency with your project notes, then confirm scope validation before final ordering. This keeps your final estimate aligned with real site conditions and reduces costly quantity revisions. Recheck dimensions, product coverage, and install requirements before purchase.
Where do I get bundles from here?+
Use the roofing square calculator or shingle bundle planner after you lock ft² or squares. For better estimating accuracy, cross-check material pricing, labor rates, and waste contingency with your project notes, then confirm scope validation before final ordering. This keeps your final estimate aligned with real site conditions and reduces costly quantity revisions.