Rate Analysis

Build the unit rate for an item by summing the costs of materials, labour and plant for the standard unit of work, then add overheads and contractor’s profit (about 10–15%).

Key formulas & points

Skim these first — then read the full notes below.

  • DAR/SSR schedule of rates for public works in states
  • Analysis of RCC, brickwork, plastering, excavation items
  • Contractor profit and contingencies typically 10–15%

Topic details

Introduction

Rate analysis determines the cost of one unit of a work item (per m³ of concrete, per m² of plaster, etc.) by adding up all its cost components. It is the foundation of estimating, because the estimate is quantities multiplied by these rates.

Scope in B.Tech and GATE syllabus

Each item’s rate combines the cost of materials (with lead and lift charges for transport), labour (from standard task-work outputs), and plant/equipment, plus water and sundries. Overheads and the contractor’s profit are then added, typically 10–15%.

Why this topic matters in practice

Governments publish schedules of rates (SSR/DAR) based on such analyses for public works, but the engineer must understand the build-up to price non-standard items and to check tenders. The coefficients of material and labour per unit come from standard data books.

Key relations & formulas

Formulas (Indian textbook notation)

  • Rateperunit=material+labour+equipment+overhead+profitRate per unit = material + labour + equipment + overhead + profit

Formulas (Indian textbook notation)

  • LeadandliftchargesformaterialtransportLead and lift charges for material transport

Formulas (Indian textbook notation)

  • Shutteringrate=costm2×numberofrepetitionsamortisedShuttering rate = \frac{cost}{m^{2}} \times number of repetitions amortised

Notation and sign conventions

Relation 1 —
Rateperunit=material+labour+equipment+overhead+profitRate per unit = material + labour + equipment + overhead + profit

Formulas (Indian textbook notation)

  • Rateperunit=material+labour+equipment+overhead+profitRate per unit = material + labour + equipment + overhead + profit
Write this relation with symbols exactly as in Estimating & Costing — BN Dutta before substituting numbers. Examiners award partial marks for a correct setup even when arithmetic slips.
Relation 2 —
LeadandliftchargesformaterialtransportLead and lift charges for material transport

Formulas (Indian textbook notation)

  • LeadandliftchargesformaterialtransportLead and lift charges for material transport
Write this relation with symbols exactly as in Estimating & Costing — BN Dutta before substituting numbers. Examiners award partial marks for a correct setup even when arithmetic slips.
Relation 3 —
Shutteringrate=costm2×numberofrepetitionsamortisedShuttering rate = \frac{cost}{m^{2}} \times number of repetitions amortised

Formulas (Indian textbook notation)

  • Shutteringrate=costm2×numberofrepetitionsamortisedShuttering rate = \frac{cost}{m^{2}} \times number of repetitions amortised
Write this relation with symbols exactly as in Estimating & Costing — BN Dutta before substituting numbers. Examiners award partial marks for a correct setup even when arithmetic slips.

Fundamentals and definitions

The material component uses the quantity of each material per unit of work (from standard mix proportions or coefficients) priced at its delivered cost; lead (horizontal haul) and lift (vertical haul) charges account for transporting materials to the work site.

Governing relations in practice

The labour component applies standard task-work or output constants — for example the number of mason- and labourer-days per cubic metre of brickwork — priced at prevailing wages; efficient rate analysis reflects realistic site productivity.

Design and analysis considerations

Plant and equipment costs cover the owning (depreciation, interest) and operating (fuel, maintenance, operator) costs, apportioned per unit of output; for reusable items like formwork, the cost is amortised over the number of repetitions.

Advanced theory and extensions

On the direct cost of materials, labour and plant, a percentage is added for overheads (site establishment, supervision) and the contractor’s profit; contingencies cover unforeseen items. The final unit rate feeds the abstract of the estimate.

Assumptions and validity limits

State assumptions explicitly before using any relation for rate analysis — steady state, uniform properties, linear elastic material, ideal gas, incompressible flow, etc., as applicable.
Wrong assumptions invalidate the entire solution even when the formula is correct. In Estimation & Costing viva and GATE descriptive questions, listing valid assumptions often earns separate marks.

Step-by-step problem approach

1. Read the question and list given data with SI units (common in Estimation & Costing papers).
2. Draw a neat labelled diagram where applicable — examiners in Indian universities award diagram marks even when arithmetic slips.
3. Identify which relation from this topic applies to rate analysis.
4. Use equation 1:
Rateperunit=material+labour+equipment+overhead+profitRate per unit = material + labour + equipment + overhead + profit
.
5. Use equation 2:
LeadandliftchargesformaterialtransportLead and lift charges for material transport
.
6. Substitute values, compute, and verify units and sign (direction).
7. State conclusion in one line — e.g. safe/unsafe, stable/unstable, feasible/infeasible.

Applications & exam relevance

Rate Analysis appears in tendering and project billing. In Indian civil curricula this topic is tested because it connects theory to quantity surveying and valuation.
GATE and semester exams often combine rate analysis with earlier units — revise prerequisites before attempting mixed problems.
Industry interview panels sometimes ask: "Where did you use rate analysis?" — answer with a lab, mini-project, or plant visit example if possible.

Common mistakes in exams

• Omitting lead and lift (transport) charges for materials.
• Using unrealistic labour output constants for the site conditions.
• Forgetting to amortise formwork cost over its number of reuses.
• Leaving out overheads, contingencies or contractor’s profit.

Quick revision checklist

Before attempting rate analysis problems, confirm you can:
1. DAR/SSR schedule of rates for public works in states
2. Analysis of RCC, brickwork, plastering, excavation items
3. Contractor profit and contingencies typically 10–15%
Revise the solved examples in Estimating & Costing — BN Dutta and one previous-year GATE or university paper for this unit.

Worked examples

Try the problem first — open the solution when you are ready to check.

Unit rate build-up for an item

Problem

For 1 m³ of an item the material cost is ₹3200, labour ₹1500 and plant ₹300. Overheads and contractor’s profit are taken as 15% of the direct cost. Compute the unit rate.

Solution

Direct cost = material + labour + plant = 3200 + 1500 + 300 = ₹5000 per m³. Overheads and profit = 15% × 5000 = ₹750. Unit rate = 5000 + 750 = ₹5750 per m³. This rate, multiplied by the measured quantity of the item, gives its cost in the abstract of the estimate.

Conceptual check — Rate Analysis

Problem

In a Estimation & Costing semester or GATE paper you are asked: "State the main assumption, the governing relation, and one practical consequence of rate analysis." What should a complete answer include?

Exams & GATE

BN Dutta — prepare rate analysis for standard items.

📖 Standard books (India)

  • Estimating & CostingBN Dutta

    Read: Syllabus unit

    Quantity surveying and rate analysis