Analysis of rates for building works is the process of separation of works into components/elements (Viz. Labour, materials, machinery,transport, overheads and profit) of work and pricing them.
Analysis of rates is required for:
- Insertion in a tender (i.e.) as a lump sum, item rates
- To check reasonability of rates inserted by tenderers
- To assess various quantities of labour, materials, machinery, money and to effect economy by using alternatives and to optimize the resources
- To assess the rates payable for deviations, extra items of work to the builder
- To compare the costs with sanctioned amount and to take action for regularization of excess/ less cost
- To workout the budget and cash flows at various stages of the work and arranging interim/ final payments
- To detect irrational rates quoted by tenderers
- To serve as basic data in case of disputes that may arise at a later stage
Analysis of rates consists of rates of following elements:
a) Material cost inclusive of wastage
b) Labour cost
c) Plant & machinery owning and operating charges
d) Water charges
f) Insurance/ risk coverage charges
g) Contractor’s overheads and profit
Following points are considered while preparing analysis of rates:
1. Percentage profits & overhead charges:
Element of profit normally varies from 5 to 10%. Overheads vary from 3 to 7 ½%. The total element of overheads and profit shall not normally exceed 17 ½% on estimated rates. This should be restricted to 10% if paid bills/ days work is considered.
2. Cement constants:
The cement constants for various items of work including wastage of 2 ½%. These constants are based on observations made by CBRI Roorkie, concrete association of India, CPWD, MES and other construction organizations. The constants are shown in Appendix ‘A’.
3. Material constants:
Cost of materials includes the supplier’s price, transportation, loading/ unloading, haulage to site, handling for incorporation into the work, wastages/breakage/pilferage, storage charges, deterioration on storage, returning of empty bags/ cases and taxes and other incidentals. The constants in use in various departments and organizations is as per Appendix ‘B’.
4. Labour output constants:
Some of the labour output constants are covered in IS – 7272. The constants given by NBO, CPWD, MES, State governments are also considered and given in Appendix ‘C’.
5. Specification of various building materials:
Generally the building materials shall conform to the relevant Indian standards. Where no such standards exist the relevant British/ American standards in so far as they are applicable could be followed. The materials of local origin (Within 40 km or distance as specified) shall be best available and approved by competent authority.
6. Basic costs: Cost of materials, labour, machinery, tools & plant (depreciated cost), and direct overheads connected to the particular project.
7. Indirect costs: Not directly related to the project but otherwise involved. The corporate office expenses, consultant charges, outsourced costs etc.
8. Daily wages: Wages which the builder is bound to pay to labour which will not be less than statutory wages.
9. All in rates: Wages + proportionate element of terminal benefits such as bonus, gratuity.
10. Standing charges: Includes element of depreciation, interest whereas running charges include cost of operation of plant, POL, operator & supporting staff.
11. Fixed/ variable overheads: fixed overheads are those incurred only once like construction of site office, where as variable overheads are salaries paid and other expenses as per employment of labour hours every month.
12. Standard schedule of rates: Many organizations/ departments shall have schedule of rates of materials/ items of works. These schedules contain specifications for materials & methods giving references to relevant Indian standards. The schedules are revised at periodic intervals of 3 to 5 years or yearly. In certain cases certain percentage addition/ deduction is specified to bring them in line with market rates.
13. Derived rates: The rates derived by interpolation/ extrapolation of rates inserted in the contract. For e.g. – The rate for PCC 1:3:6 can be derived from quoted rate for PCC 1:4:8. The rate for M-20 can be derived from quoted rate for M- 25 concrete.
14. Star rates/ Market rates: The rates worked out based on market enquiry/ quotations and applying the percentage above/ below for similar quoted trade items plus overheads and profit. Alternately rates worked out for material/ labour based on paid bills/ vouchers produced by contractor plus profit.