What a QS Does
Quantity surveyors (QSs) — also called cost managers or cost consultants — are construction professionals who specialise in the financial management of construction projects. They prepare cost estimates, manage procurement, assess contract variations, certify payments, and provide financial advice to clients and contractors throughout the construction process. For significant construction projects, a good QS is worth far more than their fee in avoided cost problems, disputes, and project overruns.
In New Zealand, quantity surveyors typically hold membership of the New Zealand Institute of Quantity Surveyors (NZIQS) and may have additional qualifications as Registered Quantity Surveyors. The profession has a long history in New Zealand’s construction industry and plays an important role on commercial and large residential projects.
Early Involvement Adds the Most Value
The most valuable QS input is at the pre-design stage — when a client is deciding whether and what to build. A preliminary cost plan based on the client’s brief and site conditions, prepared before significant design investment is made, allows realistic budget-setting that prevents the expensive rework of discovering a cost problem at tender stage. QSs who are engaged only at tender stage are validating a design that’s already locked in — the opportunity to influence cost through design decisions has already passed.
Variation Management
Construction variations — changes to the contract scope — are one of the most common sources of cost overrun and dispute. A QS who rigorously manages variation documentation — ensuring that variations are properly instructed, priced, and agreed before work is carried out — provides clients with cost certainty and contractors with fair payment for additional work. The QS’s independence from both parties makes them effective at managing this process in a way that both client and contractor trust.