Rate Analysis & Schedule of Rates (SOR)

The anatomy of a unit rate

Rate analysis is the exercise of working out what one unit of a construction item truly costs to execute — for example, one cubic metre of M20 concrete, or one square metre of 12mm internal plaster. A BOQ rate is never a guess; it is built up from four components.

Material: the quantities of each material needed for one unit, priced at current market rates, plus a wastage allowance. For one cubic metre of M20 concrete by nominal mix you account for cement (bags), fine aggregate (sand) and coarse aggregate (jelly) in their mix proportions, with typical wastage of around 2-5% added on.

Labour: the crew and time needed per unit — mason, unskilled helpers (beldars), bar benders, mixer operators — costed against daily wage rates. Standard references give an "output per day" or coefficient for each trade, which is how you convert a day-rate into a per-unit labour cost.

Machinery and sundries: mixer, vibrator, water, small tools and consumables, apportioned per unit. Add material + labour + machinery and you get the prime cost. On top of that go overheads and profit.

Overheads, profit and the final rate

The prime cost is only what the item physically consumes. A contractor also has to cover the cost of running the business and make a margin, or the project is not viable.

Overheads split into two kinds. Site (or field) overheads are project-specific: site office, supervision salaries, temporary electricity and water, scaffolding, safety gear, insurance. General (or head-office) overheads are the share of the firm running costs — office rent, accounts staff, statutory compliance — spread across all live projects. Together these are commonly loaded on as a percentage of prime cost.

Profit is then added as a further percentage. In Indian practice a combined loading for overheads and profit in the rough range of 10-15% on prime cost is typical, though it varies widely with project size, competition and risk. A tight, competitive tender might carry a thinner margin; a small, risky or fast-track job carries more.

So the final BOQ rate = material + labour + machinery (= prime cost) + overheads + profit. Understanding this build-up is what lets you defend your rate to a client, or spot when a competitor has quoted below cost and will likely cut corners or claim extras later.

What a Schedule of Rates (SOR) is and why it matters

Doing full rate analysis for every item on every project would be exhausting, and it would make pricing wildly inconsistent between estimators. A Schedule of Rates (SOR) solves this.

An SOR is a published, standardised list of pre-analysed rates for common items of work, maintained by an authority — the state PWD (Public Works Department), CPWD (Central Public Works Department) at the national level, or bodies whose schedules many states and agencies reference. It gives an official rate per unit for, say, "RCC M25 in columns" or "12mm cement plaster", based on standardised material coefficients, labour outputs and a notified rate of basic materials and wages for that region and year.

Why it matters: SOR standardises pricing so that government and large private tenders can be estimated, compared and audited fairly. It removes arbitrary pricing, gives a defensible baseline for negotiation, and provides the "analysis of rates" documents that show exactly how each SOR item was built up. Because material and labour prices move, SORs are revised periodically and often adjusted with a cost index or star-rate for items not in the schedule. For a pro, quoting against the current SOR — and knowing where your actual costs sit above or below it — is the backbone of competitive, credible estimating.