Many people dream of buying a plot of land and constructing their own house. But doing so is no easy feat. One has to understand all the intricacies of the building construction process, such as the process of estimation that will help determine the quantities and costs of various materials, labour, and overheads required for the construction of a structure.
One of the methods of estimation is based on the dimensions of the walls of the building. In this method, the walls are classified into two types: long wall and short wall.
In this blog, we will learn more about this method of estimation. Let us begin!
Defining Long Wall and Short Wall
A long wall is a wall that runs along the length of the building. On the other hand, a short wall is a wall that runs along the width of the building. The length and width of the building are measured from the centre line of the walls. The centre line is an imaginary line that passes through the middle of the thickness of the wall.
The advantage of using the long wall and short wall method is that it simplifies the calculation of the area and perimeter of the walls, as well as the openings such as doors and windows. The area and perimeter are used to determine the quantities of materials such as bricks, mortar, plaster, paint, etc.
Long Wall and Short Wall Estimation: The Process
The steps involved in estimating a building using long wall and short wall method are:
- Draw a plan of the building showing the centre line of the walls, dimensions, and openings.
- Divide the walls into long walls and short walls according to their orientation.
- Calculate the length of each long wall and short wall by adding or subtracting half of the thickness of the adjacent walls from the centre line dimensions.
- Calculate the height of each wall from the floor level to the ceiling level.
- Calculate the area of each wall by multiplying the length and height.
- Deduct the area of openings such as doors and windows from the area of each wall.
- Calculate the perimeter of each wall by adding the length of all sides.
- Multiply the area and perimeter by the respective unit rates of materials, labour, and overheads to get the cost of each wall.
- Add up the cost of all walls to get the total cost of estimation.
Benefits of Using Long Wall and Short Wall in Estimation of Building
As we have learned so far, estimation helps in planning, budgeting, and controlling the project. Thus, it pays to go over the advantages of various estimation processes, such as long wall and short wall, before settling for the right one.
The long wall and short wall method has some benefits over other methods of estimation, such as:
- It is simple and easy to understand and apply.
- It is suitable for buildings with regular shapes and dimensions.
- It reduces the chances of errors and omissions in measurements.
- It gives a fair idea of the total cost of the building.
However, the long wall and short wall method also has some limitations, such as:
- It is not accurate for buildings with irregular shapes and dimensions.
- It does not account for openings, projections, recesses, and other features in the walls.
- It does not consider the wastage and losses of materials during construction.
- It does not include the cost of foundations, roofs, doors, windows, and other components of the building.
Conclusion
Overall, the long wall and short wall method is a useful technique for estimation of building, but it should be used with caution and cross-checked with other methods for accuracy and completeness.
Some things to consider when using this method are:
- It is suitable for rooms that have rectangular or square shapes, and have uniform heights and widths.
- It may not be accurate for rooms that have curved, inclined, or irregular walls, or have different heights and widths.
- It may not account for variations in brick sizes, mortar thickness, or workmanship quality.
- It may not include other materials such as reinforcement, plastering, painting, etc.
- It may not reflect the actual cost of materials and labour in your location.
Therefore, it is advisable to use this method as a rough estimate only, and consult a professional engineer or contractor for more accurate and detailed calculations.