When figuring quantities, remember to double check your measurements, allow for compaction (equals higher yield per CY), allow for a waste factor and always round up.
General Quantity Formulas:
Length x Width = Square Feet
Square Feet x Depth = Cubic Feet
Cubic Feet / 27 = Cubic Yards
Example 1:
Standard Driveway or Pad to be
covered with Stone, 6″ Deep
15′ x 25′ = 375 Square Feet
375′ x .5 (6″ Depth) = 187.5 Cubic Feet
187.5 / 27 = 6.94 Cubic Yards (round up
to 7 yards)
Example 2:
L-Shaped Driveway or Pad to be
covered with Stone, 7″ Deep
This would be done in two
sections.
18′ x 40′ = 720 Square Feet
10′ x 40′ = 400 Square Feet
400′ + 720′ = 1,120 Square Feet
1,120 x .58 (7″ Depth) = 649.60
Cubic Feet
649.60 / 27 = 24.06 Cubic Yards
Square Footage Inside of a Circle:
Length x Width x .7854 = Square Feet
Example:
24′ Round Swimming Pool
24′ x 24′ = 576′
576′ x .7854 = 452.39 Square Feet (total inside pool)
To add 4″ of sand evenly across pool:
452.39′ x .33 (4″ depth) = 149.29 Cubic Feet
149.29 / 27 = 5.53 Cubic Yards
To be safe, always round up. You would order 6 Cubic Yards of sand.
Length Around a Circle:
Diameter x 3.1416 = Linear Feet Around a Circle
Example:
Length Around a Circle, 18′ Round
Swimming Pool
18′ x 3.1416 = 56.55′ (total linear feet around pool)
To add 2′ of stone around this pool 3′ deep:
56.55′ x 2′ = 113.10′
113.10′ x .25 (3″ depth) = 28.28 Cubic Feet
28.28 / 27 = 1.05 Cubic Yards