A School Toilet Quotation That Is 'Too High' - But Is It?
A plumber submits a lump-sum quotation of ₹87,500, inclusive of 18% GST, for a school toilet block with 6 WCs, 4 urinals and 6 wash basins. The attached schedule lists 25 mm GI inlet pipe 40 m at ₹180/m, 110 mm PVC drain 35 m at ₹220/m, 15 mm CPVC branches 60 m at ₹95/m, WC ₹3,200 each, urinal ₹1,800 each, wash basin ₹1,500 each, and fittings ₹6,000. Labour is to be charged at 20% of material and wastage at 5% on pipes and fittings. The approved drawing, however, scales to 52 m of inlet and 41 m of drain, and the sanitary fixtures are to be connected with concealed cisterns and bottle traps that are not listed. The school engineer compares only the lump sum with a rival's ₹92,000 and calls the plumber's quote 'too high'. The plumber must either justify or revise the estimate before the tender closes.
1. Recalculate the quotation from the listed rates and the drawing quantities, showing wastage, labour and GST, and identify the errors in the original figure.
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Measured quantities
- 25 mm GI inlet: 52 m × ₹180 = ₹9,360
- 110 mm PVC drain: 41 m × ₹220 = ₹9,020
- 15 mm CPVC branches: 60 m × ₹95 = ₹5,700
- Pipe subtotal = ₹24,080
- Fittings = ₹6,000
- Pipes + fittings = ₹30,080
- Wastage at 5% = ₹1,504
Sanitary fixtures
- 6 WCs × ₹3,200 = ₹19,200
- 4 urinals × ₹1,800 = ₹7,200
- 6 wash basins × ₹1,500 = ₹9,000
- Fixture subtotal = ₹35,400
Totals
- Material = ₹30,080 + ₹1,504 + ₹35,400 = ₹66,984
- Labour at 20% = ₹13,397
- Subtotal = ₹80,381
- GST at 18% = ₹14,469
- Total = ₹94,850 (rounded)
Errors in the original quotation The original used 40 m instead of 52 m of inlet and 35 m instead of 41 m of drain, under-measuring 18 m of pipe. It also omitted concealed cisterns and bottle traps. At ₹87,500 the quote is about ₹7,350 below the correctly measured figure, not above it. The engineer's comparison is therefore misleading: the rival's ₹92,000 may itself be under-scoped.
2. Prepare a short revised summary the plumber can submit, explaining why the total has changed and what assumptions are made.
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Revised summary to submit
- Material as measured: ₹66,984
- Labour at 20% of material: ₹13,397
- Subtotal: ₹80,381
- GST at 18%: ₹14,469
- Grand total: ₹94,850
Reasons for the change
- Pipe lengths have been re-measured from the approved drawing: 52 m inlet and 41 m drain, not 40 m and 35 m.
- Concealed cisterns and bottle traps are now included as required by the fixture specification.
- Wastage at 5% is applied to pipes and fittings only, as stated.
Assumptions to state Rates are inclusive of ordinary fittings but exclude civil chasing, making good, tiling and electrical work. The quote is based on joint measurement before billing. The original ₹87,500 should be withdrawn rather than defended, because executing that scope at that price would force substandard materials or unpaid extra work.
3. Advise the plumber on what the revised quotation should contain to avoid disputes during execution and payment.
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The revised quotation should be a small contract, not a single figure.
- Measurement basis: state that pipe lengths are measured along the centreline of the pipe, not along the wall, and that fixtures are counted as installed and tested.
- Scope and exclusions: list concealed cisterns, bottle traps, chasing, making good, tiling, electrical connections and dismantling of old work as included or excluded.
- Testing and handover: include pressure testing, flushing and disinfection, and a defect-liability period, for example 12 months on workmanship.
- Payment terms: specify a mobilisation advance, stage payments against measured work, and retention until handover.
- Variation procedure: any extra work to be priced and approved in writing before execution.
- GST and rates: show GST separately and state the validity of rates.
Finally, invite the engineer to compare scopes line by line rather than lump sums. A low lump sum with an unclear scope is the main cause of site disputes and of unsafe shortcuts in school sanitation work.