Importance of center line method in estimation

In this construction video tutorial, S.L.Khan, the renowned engineer, presents a useful video that briefly explains the concept of the Center Line Method Of Measurement.

With centerline method, calculation for earthwork, concrete work or brick work for all walls of the building can be accomplished simultaneously. If junctions exist, calculation should be done cautiously by deducting the widths.

Centerline method facilitates to get rid of tedious lengthy mathematical calculations and make calculations rapidly.

Normally, the purpose of the center line method of measurement (CLM) is to find out the center line length of object or member. As for example center line length of road, center line length of sewer line , center line length of building wall etc. As soon as it is accomplished then the estimation should be done for anything that is associated with quantity or estimation. In brick work of a wall, the length, breath and width (length x breath x width) of the wall or member are multiplied. Therefore, in this formula the length means the center line length.

As for example, if you are going to calculate the volume or quantity of a road sub base with following formula :-

Volume of road sub base = cross section area x length
Cross sectional area can be written as breadth x thickness x length
Now, the problem is what length (external or internal) should be considered ?

If external length is considered, the quantity will be maximum whereas for internal length the quantity will be minimum as compared to external length.

But if you consider centerline length, the quantity will be perfect. You can put the center line length as the length of the road.

To get more information on center line method, go through the following video tutorial.

Video Source: SL Khan