The difference between architectural design and working drawings in a residential build

There are three distinct types of drawings in a New Zealand residential design and build process. Concept drawings establish the idea. Consent drawings, also called resource consent or building consent drawings, meet Auckland Council's requirements to grant consent. Construction drawings, also called working drawings, tell the builder how to build. Each type has a different purpose, a different level of detail, and a different cost to produce. Most disputes about what the architect was supposed to deliver can be traced to confusion about which type of drawing the client thought they were getting.

What are concept drawings and what do they show?

Concept drawings establish the architectural intent of the project. They typically include floor plans, elevations, and sometimes sections, all at a scale sufficient to understand the spatial arrangement, the form, and the general character of the design. They are not dimensioned in full. They do not show every window size, every structural detail, or every room height. They exist to communicate the design idea and to allow the client to make informed decisions about whether the concept meets their brief.

Concept drawings are used internally by the design team and shared with the client for feedback and approval. They are also used by the builder for early-stage cost estimation. A builder asked to price a project from concept drawings is working from limited information, which means their estimate will carry a wide uncertainty range. That is normal at this stage. Do not treat a concept-stage estimate as a contract price.

What do consent drawings include that concept drawings do not?

Consent drawings must satisfy the requirements of the Building Act 2004 and the specific checklist items Auckland Council requires for your project type. That means full dimensioned plans, sections, and elevations; a site plan showing setbacks to all boundaries confirmed against the Auckland Unitary Plan; a weathertightness design under E2/AS1 of the New Zealand Building Code; window and door schedules; structural drawings and calculations signed by a chartered professional engineer; a producer statement from the structural engineer; schedules of materials and cladding systems; fire safety measures where required; and specific details that Council requires for any non-standard element of the design.

Producing this document set from a concept takes two to four months of design work, depending on project complexity. It involves significant input from the structural engineer and, on technically complex projects, from specialist consultants for fire engineering, acoustic design, or geotechnical assessment. This is why consent drawings cost substantially more to produce than concept drawings and why the architect's fee for the consent stage is typically larger than the fee for the concept stage.

What are construction drawings and why are they different again?

Construction drawings add all the technical detail that subcontractors need to build to the required standard. They expand on the consent drawings with full joinery details, setting-out dimensions, services coordination, fit-out details, connection details between elements, finishing schedules, and all the information that translates the consented design into precise instructions for the people actually doing the work.

Not all architects produce full construction drawings as part of their standard service. Some deliver the consent set and then provide limited additional detail. Others produce a full construction drawing set as a separate deliverable. This distinction matters enormously for the builder and, by extension, for the client's final cost. A builder working from a consent set without full construction drawings makes more decisions in the field. Some of those decisions will not match what the architect intended. The result is either variations or disputes.

On W O Flatz Construction projects, we require sufficient drawing detail to build from before we start each significant stage of work. If the architect has not produced construction drawings for a particular element, we identify that gap and resolve it before work starts rather than interpreting it on site. This is partly a quality issue and partly a cost-control issue: decisions made at the drawing stage are cheap. Decisions made after work has started are expensive.

What is revision control and why does it matter?

Drawing revision control is the process of managing updates to drawings throughout the design and construction process. Every drawing should have a revision number and date, and the builder and all subcontractors should be working from the same current revision at all times. When drawings are updated, the revision should be clearly identified and the updated drawings distributed to everyone who needs them.

Poor revision control is a consistent source of construction errors. A carpenter who frames from revision C drawings when the engineer has issued revision E structural drawings will build something that does not match the current structural design. That error costs money to fix and creates consent compliance questions at inspection.

On a well-run project, the architect maintains a drawing register that shows the current revision status of every drawing. The builder checks that register before starting each work stage. This is basic but critical project management, and it requires both the design team and the builder to take it seriously.

What does each drawing stage cost in architect fees?

Architect fees for residential projects in New Zealand are typically calculated as a percentage of construction cost, ranging from 8 to 15 percent for a full-service engagement from concept to construction observation. Concept design accounts for roughly 20 percent of that fee. Consent documentation accounts for 30 to 40 percent. Construction drawings and contract administration through the build account for the remainder.

The specific percentages vary by architect and by the complexity of the project. What matters for the client is understanding what stage the architect's scope covers before signing the design engagement. An architect engaged only to concept stage cannot produce the consent set without an additional fee agreement. An architect engaged to produce a consent set but not construction drawings will not be producing the detail that subcontractors need without additional scope and fees.

Read your architect's engagement letter carefully. Identify what drawing deliverables are included at each stage, what is excluded, and what triggers additional fees. Ask these questions before work starts, not when the builder says the drawings are insufficient to build from.