A builder and quantity surveyor brought in after the design is finalised can only ever react to decisions that have already locked in the project’s cost and buildability. Brought in earlier, both can genuinely influence the outcome. Here’s where that dividing line actually sits.
What Happens When Delivery Expertise Arrives Too Late
By the time architectural drawings are complete and a resource consent application is underway, the core design, unit mix, and site layout are largely fixed. If a builder or QS only sees the project at this point, their role shrinks to pricing what’s already been drawn — rather than helping shape a design that’s genuinely efficient to build.
The Earlier Involvement Point
Bringing in a builder and QS during concept design — while unit configurations, shared boundaries, and site layout are still flexible — allows buildability and cost feedback to shape the design itself, rather than being discovered as a problem after drawings are locked in. This is where sequencing, shared-wall considerations, and site access constraints are still cheap to adjust.
What a Quantity Surveyor Adds at This Stage
- Cost feedback on unit mix and configuration options before they’re finalised
- Early identification of cost drivers specific to multi-unit delivery (shared services, fire separation, access requirements)
- A realistic budget benchmark to test design decisions against, rather than a single number produced after design is complete
What a Builder Adds at This Stage
- Buildability feedback on sequencing across multiple units
- Early flagging of site access and staging constraints that affect programme
- Practical input on shared boundary and party-wall considerations before they’re designed in
A Simple Way to Think About Timing
| Project stage | Value of involving a builder/QS now |
|---|---|
| Concept design / unit mix still flexible | High — can genuinely influence design and cost |
| Drawings finalised, consent underway | Moderate — can flag issues but design changes become costly |
| Consent granted, ready to tender | Low — role is largely limited to pricing and delivery |
Frequently Asked Questions
When should a builder be involved in a multi-unit development?
Ideally during concept design, while unit mix, configuration, and site layout are still flexible enough for buildability and cost feedback to genuinely influence the outcome.
What does a quantity surveyor do before construction starts?
A QS provides cost feedback on design options, identifies likely cost drivers specific to the project type, and establishes a realistic budget benchmark to test decisions against as the design develops.
Is it too late to involve a builder if drawings are already finalised?
Not too late to get useful pricing and delivery input, but the ability to influence design decisions that affect cost and buildability is significantly reduced once drawings are locked in.
Planning a multi-unit development and weighing up timing? Get in touch to discuss your project, or read more about our multi-unit delivery experience.