How to Calculate Area and Perimeter of Different Shapes


In this exclusive civil engineering article, you will learn how to measure the area of different shapes in the construction site from related construction drawings.

The article focuses on various formulas for area calculation. It will help you to measure the area for plastering, painting works in construction.

To determine the area of a rectangular shape, the following formulas are used:-

For perimeter = 2(a+b)

For area = a x b

To determine the area of a square shape, the following formulas are used:-

For perimeter = 4a

For area = a2

To determine the area of a triangle shape, the following formulas are used:-

For perimeter = a + b + c = 2S

For area = ½ x b x h

To determine the area of a right triangle, the following formulas are used:-

For perimeter = b + h +d (here, b denotes base or length, h denotes height & d denotes distance)

For area = ½ x b x h

To determine the area of a equilateral triangle, the following formulas are used:-

For perimeter = 3a

For area = 1-1/2 bh or 2 - √3/4a2

To determine the area of a isosceles (two sides are same & one side is different) right triangle, the following formulas are used:-

For perimeter = 2a+d

For area = ½a2

To determine the area of a parallelogram (two sides are same & one side is different) right triangle, the following formulas are used:-

For perimeter = 2(a+b)

For area = a x h

To determine the area of a rhombus, the following formulas are used:-

For perimeter = 4a

For area = ½ x d1 x d2 (here d stands for diagonal)

To determine the area of a trapezium, the following formulas are used:-

For perimeter = Sum of its four sides

For area = ½ x h (a + b)

To determine the area of a circle, the following formulas are used:-

For perimeter = 2πr

For area = πr2

To determine the area of a semi circle, the following formulas are used:-

For perimeter = πr + 2r

For area = ½πr2

To determine the area of the sector of a circle, the following formulas are used:-

For perimeter = l + 2r, here l = (θ/3600) x 2 πr

For area = (θ/3600) x πr2

area and perimeter