08/12/2025
ESTIMATES💲USED IN CONSTRUCTION AND CIVIL ENGINEERING WORKS.🏗🦺
Construction and civil engineering use various estimates from rough conceptual stages (Preliminary, Plinth Area, Cube Rate) to highly detailed ones (Detailed Estimate, Item Rate), serving different purposes like feasibility, bidding, and cost control, including specific types for repairs (Annual Repair) or project changes (Revised, Supplementary).
These estimates progress from general overviews with wide variance to precise calculations using measured quantities and rates.
APPROXIMATE/PRELIMINARY ESTIMATES
1. Preliminary/Rough Order of Magnitude (ROM) Very early, high-level cost for feasibility, using limited info (e.g., cost per square meter/feet).
2. Plinth Area Estimate
Based on building's plinth area and historical rates per plinth area.
3. Cube Rate Estimate (Cubical Content)
Plinth area multiplied by height; useful for multi-story buildings.
4. Approximate Quantity Method
Estimates based on total length of walls or similar linear measurements.
DETAILED ESTIMATES
1. Detailed Estimate/Item Rate Estimate
Most accurate, measuring quantities of each item (e.g., concrete, bricks) from drawings and applying unit rates.
2. Quantity Estimate
Focuses on precise material quantities needed (e.g., tiles, sand).
3. Bid Estimate/Contractor's Estimate
Prepared by contractors for bidding, including overheads, profit, and risk.
4. Engineer's Estimate
Owner's/consultant's detailed estimate for comparison.
CONTROL & PROJECT MANAGEMENT ESTIMATES
[During Ex*****on]
1. Cost Control Estimate
A working estimate to track costs against the budget throughout the project.
2. Revised Estimate
Prepared when original sanctioned estimates need significant changes (scope, unforeseen conditions).
3. Supplementary Estimate
For new, unforeseen items of work not in the original estimate.
4. Final Estimate
The final calculated cost after project completion.
SPECIALIZED ESTIMATES
1. Annual Repair/Maintenance Estimate
For routine upkeep and repairs of completed works.
2. Parametric Estimate
Uses statistical relationships (e.g., cost per km of road) for large infrastructure.
3. Analogous Estimate
Uses costs from similar past projects for early-stage comparison.
