If you have a home that isn't handicapped-accessible and you have a disabled child or elderly parent, you may want to build a concrete ramp to make it easier to get into your home. When building a ramp, you need to know how much concrete you will need, so that you can make sure you have enough but avoid paying for extra. To find the amount of concrete you need, you need to know the dimensions of the ramp.
Multiply the length of the ramp times the height of the ramp. For example, if the ramp is 3 yards long and rises 1 yard, you would multiply 3 by 1 to get 3 square yards.
Multiply the result from Step 1 by 0.5 because the formula for the area of a triangle equals one-half times the base times the height. In this example, you would multiply 3 square yards by 0.5 to get 1.5 square yards.
Multiply the result from Step 2 by the width of the ramp to find the volume of concrete needed in cubic yards. Completing the example, if the ramp is 1.5 yards wide, you would multiply 1.5 square yards by 1.5 yards wide to get 2.25 cubic yards.