The Biggest Mistakes Quantity Surveyors Make in Interviews

Quantity surveying is one of the tightest markets in UK infrastructure right now, which means candidates should, in theory, hold the advantage in almost every interview. In practice, a surprising number of well-qualified QSs still lose out at the final stage, not because their experience is lacking, but because of how that experience comes across in the room. These are the patterns that come up again and again.

Mistaking a Strong CV for a Finished Interview

A CV that lists major infrastructure schemes and a solid technical background does a lot of the early work, but it is not a substitute for being able to talk through that experience live. Some candidates arrive expecting the paperwork to speak for itself and give thin, underdeveloped answers when asked to walk through a specific project. A hiring manager reading a CV wants to know the numbers add up. A hiring manager sitting across the table wants to know you can explain, clearly and on the spot, how you got there, defended a valuation, or talked a difficult subcontractor down from an inflated claim. If you cannot reconstruct the story behind your own numbers without notes, that is a gap worth closing before the interview, not during it.

Preparing for Topics Instead of Scenarios

It is tempting to revise broad subject areas, cost control, variations, final accounts, rather than preparing specific, real examples from your own project history. The problem is that most infrastructure QS interviews are built around scenario questions: how did you handle a specific disputed valuation, what did you do when a subcontractor's claim did not stack up, how did you manage cost reporting when the programme slipped. General knowledge of the topic answers none of these convincingly. Walking into the room with three or four real project scenarios you can talk through in detail, including what went wrong and what you would do differently, consistently outperforms broad revision of theory.

Talking Numbers Without Talking Contracts

Cost control cannot be separated from the contract it sits under, and interviewers notice quickly when a candidate can discuss take-offs and valuations fluently but goes vague the moment a question touches on how a specific NEC or JCT clause actually applies. On UK infrastructure work, NEC forms in particular govern how delay, compensation events and payment cycles are actually handled, and a QS who cannot connect the commercial detail to the contractual mechanism underneath it will read as less experienced than one who can, even with an identical project history. If your recent experience has been on one contract form, it is worth being honest about that rather than overstating familiarity with a form you have not actually worked under.

Treating It as a One-Way Technical Test

An interview for a commercial role is, by its nature, a commercial conversation, not an oral exam. Candidates who treat it purely as a test of correct answers, rather than a two-way discussion about how they would operate within the team and the client relationship, miss an opportunity to demonstrate exactly the skill the role requires. QSs manage subcontractors, negotiate variations and sit in meetings with people who do not want to hear what the numbers say. Interviewers are often watching for how a candidate handles pushback, ambiguity or a question they were not expecting, as much as whether they can recite the right process.

Running Too Hot or Too Quiet

Interview nerves affect people differently, and both extremes cause problems. Some candidates over-explain, walking through every measurement detail of a take-off until the interviewer loses the thread of the actual point being made. Others clam up under pressure and give answers so brief that a genuinely strong track record ends up sounding thin. Neither extreme reflects well, and both are usually fixable with practice: rehearsing answers out loud, ideally with someone else asking follow-up questions, does far more good than reading through notes silently.

Forgetting the Interview Runs Both Ways

Ending an interview without asking anything meaningful is a missed opportunity, particularly in a market where experienced QSs can be genuinely selective. Asking about the upcoming project pipeline, how cost reporting works day to day on the account you would be joining, or what has caused disputes or delays on similar schemes recently signals genuine commercial curiosity, and it gives you real information to decide whether the role is actually right for you. Passive, disengaged closing questions, or none at all, leave the opposite impression.

Generic answers that ignore current conditions, material cost pressure, the specific funding cycle a project sits under, regional labour availability, tend to stand out for the wrong reasons. Infrastructure clients want QSs who understand the market they are actually operating in right now, not a theoretical version from a textbook or an old training course. Referencing current, specific realities, even briefly, shows a level of commercial awareness that generic preparation simply cannot fake.

The Common Thread

Almost every mistake on this list comes back to the same root cause: preparing to demonstrate knowledge, rather than preparing to have a genuine, specific conversation about how that knowledge has actually been applied. In a market as candidate-favourable as infrastructure quantity surveying is right now, the QSs who consistently get offers are rarely the most qualified on paper. They are the ones who can talk through their own experience clearly, connect the commercial detail to the contract underneath it, and treat the interview as the two-way conversation it actually is.

If you are preparing for a QS interview and want to talk through how to present your experience, we would be glad to help.