Supplementary Estimate in Civil Engineering with Example

A supplementary estimate in civil engineering is an additional estimate prepared when there are changes in the project scope, unforeseen conditions, or design modifications that were not accounted for in the original estimate. It serves as an adjustment to the initial budget and is typically required when unforeseen expenses arise during construction.

Example:

Consider a project for constructing a 2-story residential building, where the original estimate was ₹10,00,000. During construction, certain changes or unforeseen conditions necessitate a supplementary estimate.

1. Unforeseen Condition: Soil quality discovered to be poor, requiring additional excavation and stronger foundation design. Additional cost: ₹2,00,000.

2. Design Modification: The client requests an increase in the number of windows and a change in the interior layout, leading to higher material costs. Additional cost: ₹1,50,000.

3. Labor Rate Increase: The labor charges increase due to market fluctuation. Additional labor cost: ₹50,000.

The original estimate was ₹10,00,000, and the supplementary estimate adds ₹4,00,000 to the total project cost.

New Total Project Estimate = ₹10,00,000 (original) + ₹4,00,000 (supplementary) = ₹14,00,000.

Thus, the supplementary estimate brings the total cost to ₹14,00,000.

Tue Feb 4, 2025