How to determine the height of any object with ranging rods and tape

In this informative construction video tutorial, the renowned civil engineer S.L. Khan offers some useful guidelines to point a height of an object with the help of tape and ranging rod.

Suppose, the height of the object is accessible and there exist a level ground in front of it.

Assume, there are two ranging rods namely A and B. These rods are settled to some distance away from the tower.

Suppose, base of the tower is taken as T and the peak or apex of the tower is taken as P.

Now, mark two points namely C and D at the same level on the ranging rod A and B. It means AC is equivalent to BD.

Now, glance at line CD, and mark point E on the tower.

Then, view the peak of the tower from point C to mark a point D1 on ranging rod at point B.

Ensure that C, D1 and point P remain in the same straight line.

Now, with the help of same triangle rules, measure PE and then add ET to obtain the total height of the tower.

As per same triangle, PE and CE should be identical to the ratio of DD1 and CD.

Now, by multiplying CE on both sides, we get the following :-

CE x PE/CE = DD1/CD x CE

PE = DD1/CD x CE
PE = DD1/AB x AT
(As CE = AT and CD = AB)

So, the total height of tower = PT = PE + ET

To get more clear ideas, go through the following video tutorial.

Video Source: SL Khan