Introduction to the Center Line Estimation Method

The center line method is a quick and reliable way to estimate building materials. This technique calculates the total center-to-center length of walls, reducing redundancy in measurement. It helps streamline material planning, saving both time and cost.

Step-by-Step Center Line Estimation Procedure

1. Calculating Center-to-Center Wall Lengths

Long Wall Calculation

We start by measuring the total center-to-center (c/c) length of the long wall.

Formula:

Room-1 breadth + Partition wall thickness + Room-2 breadth + (2 × ½ × wall thickness)

Calculation:

3.5m + 0.3m + 4.5m + (2 × ½ × 0.3m) = 8.6m

Short Wall Calculation

Next, compute the short wall length.

Formula:

Room length + (2 × ½ × wall thickness)

Calculation:

5m + (2 × ½ × 0.3m) = 5.3m

Partition Wall Length

The partition wall spans the full room length:

Length = 5m

2. Important Consideration

Do not add the wall width again for the partition wall. It’s already included in the long wall’s center line. Overlapping this portion will inflate your estimate.

3. Total Center Line Length

Formula:

(2 × long wall) + (2 × short wall) + partition wall

Calculation:

(2 × 8.6m) + (2 × 5.3m) + 5m = 17.2m + 10.6m + 5m = 32.8m

This total forms the base of all further calculations.

Material Quantity Estimation Based on Center Line Length

1. Excavation Volume

Formula:

Center line length × Breadth × Total depth

Calculation:

32.8m × 1.2m × (0.15m + 0.55m) = 32.8m × 1.2m × 0.7m = 27.552 cubic meters

2. PCC (Plain Cement Concrete)

Formula:

Center line length × Breadth × Thickness

Calculation:

32.8m × 1.2m × 0.15m = 5.904 cubic meters

3. Foundation Concrete Volume

Formula:

Center line length × Breadth × Depth

Calculation:

32.8m × 0.9m × 0.55m = 16.236 cubic meters

4. Plinth Wall Volume

Formula:

Center line length × Breadth × Height

Calculation:

32.8m × 0.6m × 0.45m = 8.856 cubic meters

5. Superstructure Wall Volume

Formula:

Center line length × Wall thickness × Height

Calculation:

32.8m × 0.3m × 3m = 29.52 cubic meters

Center Line Method Estimation Table

Click Here To See How To Calculate Center-to-Center Distance Between Reinforcement Bars