---
title: "Revised vs supplementary estimate"
subject: "Estimating and Costing"
chapter: 3
key: "semester_7/estimating_and_costing:revised-vs-supplementary"
source: https://www.bctengineer.com/q/semester_7/estimating_and_costing/revised-vs-supplementary
site: BCT Engineering
---

# Revised vs supplementary estimate

Estimating and Costing · Chapter 3: Types of Estimate

- Asked in: 2082 Bhadra, 2+4 marks
- Video: [Difference between Revised Estimate & Supplementary Estimate (QSC) - [HINDI]](https://www.youtube.com/watch?v=T-Cl2WTQolA) — Learn Civil Tech & Tricks
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_7/estimating_and_costing/revised-vs-supplementary
- Whole chapter: https://www.bctengineer.com/md/semester_7/estimating_and_costing/chapter-3

## Question

List the various types of estimates. Differentiate between revised estimate and supplementary estimate for a project.

## Short answer

Types: preliminary, detailed, revised, supplementary, complete, annual repair, extension/improvement. A revised estimate replaces the original sanction when costs exceed the permitted limit (e.g., design change), covering the whole work; a supplementary estimate adds new work not in the original scope, leaving the original estimate valid.

## Answer

#### Types of estimates
1. Preliminary (approximate) estimate
2. Detailed estimate
3. Revised estimate
4. Supplementary estimate
5. Complete estimate
6. Annual repair and maintenance estimate
7. Extension and improvement estimate

#### Revised versus supplementary estimate
| Basis | Revised estimate | Supplementary estimate |
|---|---|---|
| Meaning | New estimate that replaces the original sanctioned estimate | An additional estimate for extra work over the sanctioned one |
| Reason | Original cost will be exceeded (rate rise, design or quantity change) | New work not in the original estimate is needed during construction |
| Effect on original | Original is cancelled and replaced | Original remains valid; the new one is added to it |
| Scope | Covers the whole work (changed items and unchanged) | Covers only the additional items |
| Limit | Usually when cost exceeds the sanction by about 5% | Prepared whenever extra work is required |
| Example | Foundation deepened, cost rises, whole estimate redone | Boundary wall added to a building project |

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What happens to the original estimate under a revised estimate and a supplementary estimate respectively?
   A. Revised cancels and replaces it; supplementary leaves it valid and adds to it
   B. Revised adds to it; supplementary cancels it
   C. Both cancel it
   D. Both leave it unchanged
   Answer: A. Revised replaces; supplementary supplements. (Key point: Effect on original)

2. Which estimate covers only the additional items?
   A. Revised estimate
   B. Supplementary estimate
   C. Preliminary estimate
   D. Complete estimate
   Answer: B. A revised estimate covers the whole work. (Key point: Scope)

3. Adding a boundary wall to a building project is an example of:
   A. A revised estimate
   B. A preliminary estimate
   C. A supplementary estimate
   D. An annual repair estimate
   Answer: C. It is extra work not in the original estimate. (Key point: Example)

4. Which is one of the listed types of estimates?
   A. Bank loan estimate
   B. Tender negotiation estimate
   C. Contractor's profit estimate
   D. Annual repair and maintenance estimate
   Answer: D. The listed types include preliminary, detailed, revised, supplementary, complete, annual repair and extension. (Key point: Types)

## Related in Estimating and Costing

- [Revised estimate: when and why](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Arevised-estimate-when-needed) — Estimating and Costing, chapter 3, asked 3×
- [Types of estimates and when prepared](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Atypes-of-estimates-circumstances) — Estimating and Costing, chapter 3, asked 4×
- [Define project; irrigation project estimate](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Aproject-irrigation-estimate) — Estimating and Costing, chapter 5, asked 4×
- [Tasks in preparing building project estimate](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Aworks-considered-building-project-estimate) — Estimating and Costing, chapter 5, asked 2×
- [Detail estimate report for sewerage project](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Aestimate-report-sewerage) — Estimating and Costing, chapter 5, asked 2×
- [Stages of project estimate](https://www.bctengineer.com/question.md?key=semester_7%2Festimating_and_costing%3Astages-project-estimate) — Estimating and Costing, chapter 5

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