Architect vs. Structural Engineer: Roles, Responsibilities, and Importance

When a building project gets underway, two professionals tend to feature in almost every conversation: the architect and the structural engineer. Both carry legal responsibility and both influence the final outcome, but their roles are quite different. Understanding where one ends and the other begins helps owners, developers, and builders get the most from each.

What an Architect Does

An architect is responsible for the overall design of a building: how it looks, how spaces are arranged, how it will be used, and how it sits within its site and surroundings. Architects hold registration under the Architects Act 1991 (Victoria) and are legally required on most new residential and commercial projects above a threshold floor area.

Architects develop the concept, produce planning and building permit drawings, coordinate consultants, and manage the aesthetic and functional intent of a project from first sketch through to completion.

What a Structural Engineer Does

A structural engineer is responsible for making the building stand up safely under all the loads it will ever experience: gravity, wind, earthquake, occupancy, and more. Structural engineers design the skeleton of a building, which includes footings, columns, beams, slabs, and load-bearing walls, and they specify the materials, sizes, and connections needed to carry those loads safely to the ground.

In Victoria, structural engineering must be carried out by a Registered Professional Engineer of Queensland (RPEQ) or an equivalent NER-listed engineer. The structural engineer’s documentation forms part of the building permit application and is reviewed by the building surveyor.

How the Two Roles Differ

Where the Two Professions Overlap

The boundary between architecture and structural engineering is collaborative rather than rigid. A structural engineer’s choice of column grid affects the architect’s floor plan. An architect’s decision to cantilever a balcony or open up a ground floor directly shapes the structural solution required. Engaging the two disciplines together from the start avoids the rework that comes from resolving structural constraints after the design is already set.

Do You Need Both?

For most residential and commercial projects, yes. The architect leads the design process and the structural engineer provides the structural documentation required for the building permit. On some smaller projects, particularly single-storey extensions or minor alterations, a structural engineer may be engaged directly without an architect, but this depends on the scope and your council’s requirements.

Some situations where you need a structural engineer regardless of whether an architect is involved:

• Removing or modifying a load-bearing wall
• Adding a storey to an existing building
• Installing a mezzanine floor
• Building a retaining wall over 1.0 m in height
• Any new footing design in Melbourne’s Class P reactive clay soils
• Deck or pergola structures attached to an existing building

Who Do You Engage First?

For new builds and major additions, the architect typically leads the project and engages the structural engineer as part of the consultant team. For targeted structural work, such as a wall removal, a mezzanine, or a footing problem, you may engage a structural engineer directly.

Working With PBE

Principal Built Engineering works alongside architects, builders, and directly with owners across Melbourne. Whether you need structural input at concept stage, a full permit set, or a targeted solution for a specific structural problem, the approach starts with understanding what the project actually needs.