Builder Pressure on a 30-Flat Plumbing Quotation
You are a newly registered plumbing contractor. A builder asks you to quote for plumbing in a 30-flat, four-storey project. He wants a lump-sum price, no written scope, and says payment will be 'cash, no bill, so you can reduce the rate.' He also asks you to use 20 mm instead of the specified 25 mm internal risers and to skip the pressure test to save two days. Your material supplier offers a 10% discount if you buy 25 mm CPVC of a brand you have not used, with no batch test certificate. You have two helpers and one apprentice; the work must finish in 45 days. Another contractor has quoted 8% lower.
1. Identify the ethical, legal and technical issues in the builder's proposal and state how you would respond.
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The cash-without-bill proposal is tax evasion and leaves no invoice, no warranty trail and no proof of payment; it also exposes me to penalties and makes it impossible to claim against defective work. Reducing the specified 25 mm risers to 20 mm is an unauthorised design change that will increase velocity, friction loss and noise, and may fail pressure and flow requirements at upper floors. Skipping the pressure test conceals leaks and removes the evidence needed to protect both parties. Accepting cement or pipe without a batch test certificate adds unverified material risk. I would respond politely but firmly: I can quote competitively, but only with a written scope, GST invoices, the specified pipe sizes and a witnessed pressure test. Any substitution must be approved in writing by the builder's engineer, with the cost and performance effects recorded. I would not trade compliance for a lower price, because the long-term liability and reputation damage outweigh the job.
2. Outline the contents of a compliant quotation and a realistic 45-day plan with your available labour.
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The quotation should list the full scope: fixture points, pipe sizes and materials, riser and drainage routes, valves, testing, commissioning and making good. It should include measured quantities with wastage allowances, fittings, labour, supervision, overheads, profit and applicable taxes, plus payment stages, retention and validity. Exclusions and assumptions must be stated. For the programme, with two helpers and one apprentice, 30 flats in 45 days is tight. I would divide the work by floors and zones: first fix risers and horizontal runs floor by floor, then fixture setting and branch connections, then pressure testing in sections rather than one final test. Prefabrication and scheduled material deliveries with test certificates would reduce idle time. I would include a realistic allowance for curing and inspection, and state that the programme assumes uninterrupted access, power and water. If the builder refuses those conditions, the duration or the price must change.
3. How would you handle the cheaper competitor and the discounted but uncertified CPVC offer without compromising quality?
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I would not try to beat an 8% lower quote by removing testing, reducing pipe sizes or using unverified material. Instead I would explain the cost drivers in writing: certified pipe, correct sizing, pressure testing, supervision and warranty all carry real cost. If the competitor has genuinely omitted scope, my quotation can show that difference clearly. For the CPVC offer, I would ask the supplier for the manufacturer's test certificate, batch traceability and confirmation that the product meets the specified standard. If those cannot be provided, I would decline the discount and buy from an approved source, even at higher cost. I could reduce price through better procurement of standard fittings, less wastage and staged delivery, not through hidden quality cuts. If the builder still chooses the cheapest offer, I would not match it by compromising safety; I would walk away and protect my licence and reputation.