What is the Quantity Survey Method?

What is the Quantity Survey Method?

The quantity survey method is a detailed cost estimation process used in construction projects. It involves itemizing a project into components, calculating the required quantities, and estimating the cost of each component, including materials and labor. This method provides a comprehensive budget by summing these costs and often includes a contingency for unforeseen expenses.

Here's an overview of the process:

1. Itemizing Components: The first step is to break down the construction project into its individual components. This includes everything from basic materials like bricks, cement, and timber, to more complex items like electrical systems and plumbing.
2. Quantity Calculation: For each of these components, the quantity needed for the project is calculated. This is usually done by architects or engineers through detailed plans and blueprints.
3. Cost Estimation: After determining the quantities, the next step is to estimate the cost of each component. This involves researching current market prices for materials and labor rates.
4. Total Cost Calculation: Once the cost of each item is estimated, these figures are added together to arrive at a total project cost. This can also include indirect costs like transportation, storage, and management expenses.
5. Contingency Planning: Often, a contingency amount (usually a percentage of the total cost) is added to the estimate to account for unforeseen expenses or price fluctuations.
6. Regular Updates and Revisions: As the project progresses, the quantity survey may be updated to reflect any changes in design, material choices, or market conditions.

The quantity survey method is highly detailed and provides a comprehensive view of the costs involved in a construction project. This makes it a valuable tool for budgeting and financial planning, helping stakeholders understand and manage the financial aspects of construction projects more effectively.

Real World Example of the Quantity Survey Method

Below is a hypothetical real-world example of the QSM used for the construction of a residential building:

1. Project: Building a five-story residential complex.
2. Breakdown of Components: The quantity surveyor itemizes the project into various components like concrete, steel, bricks, windows, doors, electrical wiring, plumbing, and labor for each construction phase.
3. Calculating Quantities: For each item, quantities are calculated. For instance, the surveyor estimates the number of bricks needed based on the building's dimensions and the size of each brick.
4. Cost Estimation: The surveyor then researches the current market prices for each item. They find out the cost per brick, per ton of steel, per cubic meter of concrete, and hourly or daily rates for different types of labor.
5. Total Cost Calculation: By multiplying the quantities with the respective costs, the surveyor calculates the total cost for each component. They sum these to get the total project cost, including additional costs like transportation of materials and waste disposal.
6. Adding Contingency: A contingency percentage is added to the total cost to cover any unexpected expenses or price fluctuations during the construction period.

In this example, the quantity survey method provides a detailed and comprehensive budget for the residential building project, helping the developers to plan their finances and resources effectively.