Spike's Calculators

Calculate the amount of concrete needed for a column and pad using feet and inches as measurements.

Columns need to be supported by a footing. In some cases, these can be the same footings that support your foundation wall, but in most cases, they need to have a separate footing, also known as a pad. For round columns, these pads usually are square.

To calculate the volume of concrete for a column, you need the diameter and height. And for a square pad, the length of one side and the thickness (depth) of the pad.

- enter the number of columns and pads
- the diameter of the column in inches
- the height of the column in feet and inches
- length of one side of the pad in feet and inches
- depth of the pads in inches

- lineal feet of forming tube for the columns (rounded up)
- forming material for the pads, lineal feet (rounded up)
- amount of concrete needed in cubic feet
- concrete needed in cubic yards
- concrete needed in cubic metres

V = π * D² ÷ 4 * h * nfor the pad;

V = w² * d * n

where V = volume π = 3.14159..., D = diameter h = height of the column w = pad length d = pad thickness n = number of pads and columns

column diameter = 10 inches column height = 4 feet - 8 inches pad size = 28 inches x 28 inches thickness of pad = 10 inches 4 columns and pads

Since it is easier to calculate using the same units, convert the 4 feet - 8 inches into inches by multiplying the feet amount by 12 ( 12 inches in one foot);

4 * 12 + 8 = 56

4 feet - 8 inches = 56 inches

Using the formula for the columns from above;

3.14159 * 10² ÷ 4 * 56 * 4

3.14159 * 100 ÷ 4 * 56 * 4 = 17592.92 rounded to two decimals

The volume of the four columns is 17592.92 cubic inches

Using the formula for the pads from above;

28² * 10 * 4

784 * 10 * 4 = 31360

The volume of the four pads is 31360 cubic inches

Adding both results and converting the cubic inches to cubic feet by dividing the cubic inch amount by 1728 (there are 1728 cubic inches in one cubic foot)

(17592.92 + 31360) ÷ 1728

48,952.92 ÷ 1728 = 28.3 rounded to one decimal

You will need 28.3 cubic feet of concrete to pour these four columns and pads.

- Circle
- Circle - Metric
- Donut
- Donut - Metric
- Ellipse
- Ellipse - Metric
- Equilateral Triangle
- Equilateral Triangle - Metric
- Octagon
- Octagon - Metric
- Oval
- Pentagon
- Pentagon - Metric
- Scalene Triangle
- Scalene Triangle - Metric
- Stadium Shape
- Stadium Shape - Metric
- Trapazoid
- Trapezium
- Plastic Concrete Footing Form