The Tender Is Not the Project: Choosing Contractors on Evidence, Not Price
Photo: David Lally , CC BY-SA 2.0, via Wikimedia Commons
A low tender is not a bargain. It is a hypothesis about how a project will go, and it is often written by the contractor least able to test it. In UK commercial projects, the cheapest bid can become the most expensive outcome through variations, programme overruns, abortive design work, rework and the management time required to recover a failing package. Price matters, but it is a poor sole basis for shortlisting.
The argument here is not that clients should ignore cost. It is that they should stop treating the lowest number as the strongest evidence. A tender is a set of promises. The client's task is to judge which promises are credible, which are underpriced and which will be tested only after the contract is signed.
The Lowest Price Is a Promise, Not a Price
A tender price is an estimate prepared under time pressure, often with incomplete information. The contractor that submits the lowest figure may have misunderstood the scope, omitted a necessary allowance or assumed a level of access that the site cannot provide. Some will have priced the job properly and simply run a leaner operation. The difficulty is telling those cases apart before appointment.
Price-only selection encourages the wrong behaviour. It rewards optimism in the tender and discipline in the variation account. It can also push competent contractors to decline invitations, because they know they cannot win against a bid that has not accounted for the same risks. Over time, the client's tender list weakens while the apparent saving in the evaluation remains intact.
Why Price-Only Selection Fails
There are four common failure modes. The first is scope optimism: a bidder assumes the existing services are adequate, the roof is sound or the programme is achievable without temporary works. The second is capacity mismatch: the contractor wins the job but cannot resource it when the start date arrives. The third is safety and compliance shortcuts: the paperwork looks complete, but the arrangements on site do not match it. The fourth is communication failure: the client cannot get a straight answer, the reporting is late and changes are handled informally.
None of these failures is always visible in a tender sum. They become visible through evidence: comparable projects, references, accident data, programme logic, named personnel and the quality of the contractor's questions during the tender period.
A Defensible Scoring Framework
A weighted framework does not remove judgement, but it makes judgement transparent. The weightings should be published in the invitation to tender so that bidders know what will be assessed. A workable model for UK commercial projects is set out below.
| Criterion | Weight | Evidence to assess |
|---|---|---|
| Capability | 30% | Comparable projects, technical competence, references, supply-chain strength and understanding of the brief |
| Capacity | 20% | Current workload, key personnel availability, programme logic, lead times and resource plan |
| Safety | 20% | RIDDOR reportable incidents, accident frequency rate, SSIP or equivalent accreditation, quality of risk assessments and method statements, CDM 2015 experience |
| Communication | 15% | Named contact, reporting cadence, change-control process, escalation route and quality of tender queries |
| Commercial | 15% | Completeness of price, assumptions, provisional sums, day rates, cash-flow position and reasonableness against the market |
The commercial score should not simply award maximum marks to the lowest price. A better approach is to score completeness and price reasonableness, then apply a separate commercial test: is the price credible for the scope, and does it include the allowances that the project actually needs? A bid that is 20% cheaper but silent on temporary works, asbestos management or out-of-hours working is not comparable.
Safety should include a pass/fail threshold. A contractor with a weak safety record or inadequate method statements should not proceed to appointment because the arithmetic happens to favour them. The same applies to capability: a bidder without relevant experience should not be able to score highly on price alone.
Turning Scores Into a Decision
The scoring meeting should be moderated. Evaluators should score independently first, then discuss material differences and record the reasons. The audit trail matters. If the decision is challenged, the client should be able to show that the evaluation was consistent, evidence-based and conducted against published criteria.
References deserve more than a tick-box call. Ask referees about the things that matter: did the contractor resource the job, did it communicate bad news early, how did it handle variations, and would the referee appoint it again? A reference that confirms the contractor turned up is less useful than one that describes how it performed when the programme slipped.
Site visits and interviews also help. A short technical interview can reveal whether the contractor understands the building, the constraints and the client's priorities. It can also show whether the proposed project manager is the person who will actually run the job.
Price Still Matters, But as One Signal Among Several
The aim is not to make price irrelevant. It is to stop price from doing work it cannot do. A weighted framework allows a client to say, with evidence, that one contractor is stronger on capability and safety while another is cheaper but carries more delivery risk. That is a commercial judgement, not an accounting one.
The cheapest tender is often the one that has understood the least. A smarter shortlist tests capability, capacity, safety and communication before the contract is signed, then uses price as a measure of credibility rather than a substitute for it. For UK commercial clients, that is the difference between choosing a contractor and choosing a project outcome. IPM Limited advises clients on project support and contractor selection processes that are practical, documented and defensible.
