Part 1 of 2
Analysis of Rates
Last reviewed 16 Sept 2026 · 7 min read
Rate analysis — meaning and purpose
Analysis of rates is the determination of the cost per unit of an item of work (per m³, m², kg etc.) from the quantities of materials and labour required, their current rates, and allowances for tools, plant, overheads and profit.
Purposes
- Determine a reasonable rate for each item for estimates and tenders.
- Fix rates for extra/substituted items not in the schedule.
- Check the reasonableness of contractors' quoted rates.
- Revise rates when material prices or wages change.
- Prepare/update the schedule of rates.
Factors affecting rates
- Specification and quality of materials and workmanship.
- Location of the site — distance (lead) from sources of materials, transport facilities.
- Quantity of work (economy of scale).
- Labour rates and availability; local wages.
- Site conditions — working space, water, weather, height, depth.
- Profit, overheads and taxes.
- Season and time allowed for completion.
Components of a rate
| Component | Typical treatment |
|---|---|
| Materials | Quantity per unit of work (including wastage) × rate at site (cost + carriage + loading/unloading + storage) |
| Labour | Number of mason/mazdoor/bhisti days per unit (from output or task work) × daily wage |
| Tools and plant (T&P), scaffolding | Lump sum or small percentage of labour cost, or actual hire charges of machinery |
| Water charges | Commonly about 1% of the cost of materials and labour (or as per departmental rules) |
| Contractor's profit and overheads | Commonly about 10% for profit plus overheads, often combined in schedules as around 15% of the cost (as per the department's analysis) |
Percentages vary between departments and years; examinations commonly use water charges 1–1.5% and contractor's profit about 10%.
Schedule of rates and cost index
- Schedule of rates (SOR) — list of item rates approved by a department for a region and period, e.g. CPWD Delhi Schedule of Rates (DSR) and state PWD SORs, prepared by analysis of rates.
- Cost index — percentage used to update a base schedule (e.g. DSR) to the current cost level at a particular place and time; Estimated cost = base schedule amount × (1 + cost index %).
- Market rate items — items not in the schedule, analysed from market rates of materials and labour.
Material requirements
Concrete — dry volume
When dry materials (cement, sand, coarse aggregate) are mixed with water and compacted, the wet volume is less than the sum of the loose dry volumes — voids are filled.
Dry volume ≈ 1.52–1.57 × wet volume (commonly 1.54 for concrete)
For a nominal mix by volume:
Cement in bags (density of cement ≈ 1440 kg/m³; one bag = 50 kg ≈ 0.0347 m³)
Cement mortar
Dry volume ≈ 1.27–1.33 × wet volume (commonly taken as about 1.3, with some texts adding extra for wastage).
Brickwork
- Nominal (with mortar) size of a modular brick: 200 × 100 × 100 mm → about 500 bricks per m³ of brickwork.
- Actual modular brick 190 × 90 × 90 mm → volume of bricks in 1 m³ ≈ m³ → wet mortar ≈ 0.25–0.30 m³ per m³ of brickwork (commonly taken as about 0.25–0.30 m³, with the frog and wastage allowance).
- With traditional (non-modular) bricks, about 550 per m³ are commonly used in calculations; add wastage for bricks (often 5%).
Plastering
- Wet mortar = area × thickness; add for filling joints, uneven surfaces and wastage (commonly 20–30%) before converting to dry volume.
Labour — output and task work
- Task work (outturn) — amount of work one labourer or a gang can do in a day under normal conditions (e.g. m³ of excavation, m² of plaster per mason-day).
- Labour per unit of work is expressed as mason, beldar/mazdoor, bhisti (water carrier), carpenter, blacksmith days.
- Output depends on skill, climate, site conditions, height, lead — published departmental analyses give standard figures.
Worked examples (hypothetical rates)
Solution. Dry volume m³; sum of ratios Cement m³ kg ≈ 6.34 bags Sand 0.44 m³; coarse aggregate 0.88 m³
Using the quantities of Example 1 and the following hypothetical rates: cement ₹ 400 per bag; sand ₹ 1500 per m³; coarse aggregate ₹ 1800 per m³; labour for 1 m³ — 0.1 mason at ₹ 900/day, 2.0 mazdoor at ₹ 600/day, 0.7 bhisti at ₹ 600/day; T&P ₹ 100; water charges 1% and contractor's profit 10%.
Solution.
- Cement: 6.34 × 400 = ₹ 2536
- Sand: 0.44 × 1500 = ₹ 660
- Coarse aggregate: 0.88 × 1800 = ₹ 1584
- Labour: 0.1 × 900 + 2.0 × 600 + 0.7 × 600 = 90 + 1200 + 420 = ₹ 1710
- T&P: ₹ 100
Total = ₹ 6590 Water charges 1% = ₹ 65.90 → ₹ 6655.90 Contractor's profit 10% = ₹ 665.59 → Rate ≈ ₹ 7321.49 per m³
Use modular bricks (500 per m³ with 5% wastage) and wet mortar 0.30 m³ per m³ of brickwork, dry volume factor 1.30.
Solution. Bricks 525 Dry mortar m³ Cement m³ kg ≈ 1.60 bags; sand 0.334 m³
Add 30% for joints, unevenness and wastage; dry volume factor 1.27.
Solution. Wet mortar m³ → with 30% extra m³ → dry m³ Cement m³ kg ≈ 11.4 bags; sand 1.585 m³
An estimate prepared on the base schedule comes to ₹ 50 lakh. The cost index for the place is 28% (hypothetical). Find the estimated cost.
Solution. 50 × 1.28 = ₹ 64 lakh
Frequently tested points
- Rate = materials + labour + T&P + water charges (
1%) + contractor's profit (10%) and overheads. - Rate analysis used for estimates, tenders, extra items, checking quoted rates and preparing SORs (e.g. CPWD DSR); cost index updates schedules.
- Dry volume of concrete ≈ 1.54 × wet; mortar ≈ 1.27–1.33 × wet.
- Cement density ≈ 1440 kg/m³; 1 bag = 50 kg ≈ 0.0347 m³.
- 1 m³ PCC 1 : 2 : 4 needs ≈ 6.3–6.4 bags cement, 0.44 m³ sand, 0.88 m³ aggregate; 1 : 1.5 : 3 ≈ 8.2 bags.
- Modular bricks ≈ 500 per m³; mortar ≈ 0.25–0.30 m³ per m³ brickwork.
- Labour expressed as mason/mazdoor/bhisti days from task work (outturn).
- Using wet volume directly to find material quantities (forgetting the dry volume factor).
- Computing profit before adding water charges and other components (follow the order specified in the question).
- Treating illustrative rates as current market rates.
- Rate analysis finds the unit cost of each item from material and labour requirements and current prices.
- Rates include materials with wastage, labour, tools and plant, water charges, overheads and profit.
- Schedules of rates and cost indices standardise and update rates for departments and regions.
- Dry volume factors convert wet concrete and mortar volumes into cement, sand and aggregate quantities.
- Worked analyses for concrete, brickwork and plaster show the complete procedure.