Estimating Tools

How to Calculate Linear Feet Around a Circle

Formula: Diameter × 3.1416 = Linear Feet Around a Circle

Example: Length around an 18 foot diameter round Swimming Pool

1. 18 ft × 3.1416 = 56.55 ft (total linear feet around pool)
2. To add 2 feet of stone (3 inches deep) around this pool: 56.55 feet × 2 feet = 113.10 feet
3. 113.10 feet × 0.25 (3 inch depth) = 28.28 Cubic Feet
4. 28.28 ÷ 27 = 1.05 Cubic Yards

How to Calculate the Square Footage Inside a Circle

Formula: Length × Width × 0.7854 = Square Feet

Example: Square footage inside a 24 foot diameter round Swimming Pool

1. 24 feet × 24 feet = 576 feet
2. 576 feet × 0.7854 = 452.39 Square Feet (total inside pool)
3. To add 4 inches of sand evenly across pool:
   452.39 feet × .33 (4 inches depth) = 149.29 Cubic Feet
4. 149.29 ÷ 27 = 5.53 Cubic Yards
5. To be safe, always round up. You would order 6 Cubic Yards of sand.

How to Calculate Coverage for a Standard Driveway or Pad

Formula: Cubic Feet ÷ 27 = Cubic Yards

Example: Standard Driveway or Pad (15 ft. × 25 ft.) to be covered with Stone, 6 inches deep.

1. 15 feet × 25 feet = 375 Square Feet
2. 375 feet × 0.50 (6 inch depth) = 187.5 Cubic Feet
3. 187.5 ÷ 27 = 6.94 Cubic Yards (round up to 7 yards)

How to Calculate Coverage for an L-shaped Driveway or Pad

Formula: Cubic Feet ÷ 27 = Cubic Yards

Example: L-Shaped Driveway or Pad to be covered with stone, 7 inches deep. The calculation is done in two sections.

1. 18 feet × 40 feet = 720 Square Feet
2. 10 feet × 40 feet = 400 Square Feet
3. 400 feet + 720 feet = 1,120 Square Feet
4. 1,120 × .58 (7 inch Depth) = 649.60 Cubic Feet
5. 649.60 ÷ 27 = 24.06 Cubic Yards