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ছাদ উপকরণ ক্যালকুলেটর

Calculate roofing material needed in squares and bundles. Includes pitch factor and waste.

এই ক্যালকুলেটর কীভাবে ব্যবহার করবেন

  1. Roof Length (ft) লিখুন
  2. Roof Width (ft) লিখুন
  3. Roof Pitch (rise:run, e.g. 4) লিখুন
  4. Waste Factor (%) লিখুন
  5. গণনা করুন বোতামে ক্লিক করুন
  6. ক্যালকুলেটরের নিচে প্রদর্শিত ফলাফলটি পড়ুন

Understanding Roofing Squares

Roofing is measured in "squares" — 1 square = 100 square feet of roof surface. For a 2,000 sq ft roof area, you need 20 squares of material. Each square of standard shingles requires 3 bundles (about 29 shingles per bundle).

The actual roof area is larger than the footprint due to roof pitch. A roof with a 6:12 pitch covers 1.12× more area than a flat projection.

Calculating Roof Pitch Factor

Pitch is expressed as rise:run (inches of rise per 12 inches of run). Pitch factor = √(1 + (pitch/12)²). Common pitch factors:

3:12 pitch: 1.031×. 4:12: 1.054×. 6:12: 1.118×. 8:12: 1.202×. 12:12: 1.414×.

A 6:12 roof over a 1,000 sq ft footprint has 1,118 sq ft of actual surface area — 11.8% more than the flat measurement.

Roofing Material Quantities

Standard asphalt shingles: 3 bundles per square, ~240 shingles per square. For underlayment: 1 roll per 4 squares. Starter strips: linear feet of eaves + rakes. Ridge cap: linear feet of ridge ÷ 35 per bundle.

Always add 10–15% waste for standard roofs, 15–20% for complex roofs with multiple valleys, hips, or dormers.

সর্বশেষ আপডেট: March 2026

Frequently Asked Questions

How many bundles of shingles do I need for a 2000 sq ft house?

A typical 2000 sq ft house has a roof footprint of about 2000 sq ft. With a 6:12 pitch, actual roof area = 2000 × 1.118 = 2236 sq ft = 22.4 squares. Add 10% waste = 24.6 squares ≈ 74 bundles.

What is a roofing square?

One roofing square equals 100 square feet of roof surface. It's the standard unit for roofing material estimates. Shingles typically come 3 bundles per square.

How do I measure roof pitch?

Place a level horizontally on the roof. At the 12-inch mark from one end of the level, measure vertically from the level down to the roof surface. That measurement is the rise; the run is 12. A 4-inch rise = 4:12 pitch.