There are many methods used for calculating quantities of materials. Which one goes with your plan depends on the design and shape of the building. Each method is characteristically different from others. Calculation of quantities of material needs a proper technical understanding of materials and construction. The five major methods are described here for you and they come up with the right measurement of materials you need.
1- Centre Line Method: Centreline method is applicable to the square building with symmetrical offsets. To calculate the quantities of materials, you need to multiply the total centre line length with breadth and depth of the construction. The centre line length will be reduced by half of the breadth of every junction where the main wall is joined with the cross walls, partitions or verandah. The junctions must be taken into consideration while calculating the centre line length of a wall. The quantity estimation brought out by this method is accurate and fast.
2- Crossing method: Crossing method is designed for calculating materials needed for masonry walls. In this method, the lengths and breadths of walls at plinth level (the base on which a column is raised) are included. The internal dimension of the room and the thickness of the walls are also important to calculate the quantities. Symmetrical offsets should be counted as they play a major role in the calculation of the number of materials.
3- Out to out and in to in method: This method follows the P.W.D system for computing materials and this seems to be the most accurate method among all.
4- Bay method: This bay method is applicable in garages, factory, and railway platform where identical structures are visible. Bay in a construction term means a compartment of a building. The cost of one room is calculated first and it is multiplied by the number of bays.
5- Service unit method: The term service unit method is designed for building with identical rooms. This method is applicable in the construction of college, hospital, cinemas, prison, and more. When it is the construction of a hospital, the service unit will be a bed. Likewise, for cinema/stadium, it is seated.
Calculating quantities of materials follow the above-mentioned methods. Each of which shows a different perspective of calculation and they are also concentrated on different construction types.