Do I need a structural engineer to remove a load-bearing wall in NSW?

Why approval is required: load-bearing work is excluded from exempt development

Under the State Environmental Planning Policy (Exempt and Complying Development Codes) 2008 (the "Codes SEPP"), a general development standard for exempt development is that the work must not affect the load-bearing capacity of any load-bearing component of the building. Knocking out a load-bearing wall does exactly that, so it falls outside the exempt pathway. That leaves two compliant routes:

• Complying Development Certificate (CDC) — assessed and issued by a registered certifier (or council). This is the common, faster path for straightforward internal alterations to a house. The certifier will require structural plans and computations prepared by a practising structural engineer before they issue the CDC.
• Development Application (DA) — lodged with your local council where the work doesn't meet CDC standards (for example, heritage items, certain strata buildings, or sites with overlays). The council still requires engineered structural documentation.

Either way, the building work must comply with the National Construction Code (NCC) 2022. For a typical house (Class 1 building), the governing structural requirements sit in NCC Volume Two, Part H1 (Structure); apartments and commercial buildings (Class 2–9) are covered by NCC Volume One, Section B.

What the structural engineer actually designs

When a wall carries load — roof, ceiling, an upper floor, or a roof truss bearing point — that load has to be re-routed once the wall is gone. The engineer's job is to prove the new arrangement is structurally adequate and to document it for the certifier. That work is carried out to the current Australian Standards:

• AS/NZS 1170 series — Structural design actions. AS/NZS 1170.1 (permanent, imposed and other actions / dead and live loads) and AS/NZS 1170.2 (wind actions) establish the loads the new beam must carry.
• AS 4100:2020 — Steel structures. Governs the design of a steel beam (commonly a UB, UC or PFC), its connections, and any steel posts.
• AS 3600:2018 — Concrete structures. Applies where a concrete beam, slab support or new footing/pad is involved.
• AS 1684.2:2021 — Residential timber-framed construction. Relevant to timber lintels, wall framing and tie-downs in houses up to the standard's scope.
• AS 1720.1 — Timber structures. Used where an engineered (e.g. LVL or glulam) timber beam is specified rather than a sawn timber member sized from span tables.

The deliverable is a stamped set of structural drawings and a design certificate (and supporting computations) that the certifier relies on to issue the CDC or that council needs for a DA. Where new footings or a pad are required under a post, the engineer will also confirm bearing adequacy.

Is the wall even load-bearing? Don't assume

Not every wall is structural, but the wrong guess is expensive and dangerous. Indicators a wall is load-bearing include: it runs perpendicular to the floor joists or roof trusses above; it sits over a beam, footing or another wall on the storey below; or it supports a roof strut or hanging beam. A structural engineer (or a builder under engineering advice) should confirm this on site before anything is opened up. Treating a load-bearing wall as a "stud wall" and removing it without a designed beam can cause sagging, cracking, or collapse — and it will fail certification.

Builder licensing and insurance also apply

Removing a load-bearing wall is residential building work under the Home Building Act 1989 (NSW). Practically that means:

• Residential building work valued over $5,000 must be carried out by an appropriately licensed builder or tradesperson (NSW Fair Trading licensing).
• Where the contracted work exceeds $20,000, Home Building Compensation (home warranty) insurance and a written contract are required.
• An owner-builder permit is needed where you manage the work yourself above the relevant threshold — but you still need the engineered design and building approval.

The engineering and certification are separate from the builder's licence: you need both the designed beam (engineer) and a licensed builder to install it, and a certifier to sign off.

The typical sequence

1. Site assessment — confirm the wall is load-bearing and identify what it supports.
2. Structural design — engineer sizes the beam, posts and any new footings to AS/NZS 1170, AS 4100, AS 3600, AS 1684/AS 1720 as applicable, and issues stamped plans.
3. Approval — certifier issues a CDC (or council assesses a DA) using those plans.
4. Construction — licensed builder installs temporary props, then the beam, then makes good. Temporary propping during the works should itself be adequate; on larger or staged jobs that propping is engineered too.
5. Sign-off — occupation/compliance certificate on completion.

Metric Engineering handles the structural design and certification for load-bearing wall removals across Greater Sydney — beam sizing, connection details, footings, and the stamped documentation your certifier needs. We can also design the temporary propping where the job warrants it.

Reviewed by Youssef Emad, MIEAust 5372671, Registered Professional Engineer (NSW) PRE0002581, RPEQ 37639, Metric Engineering. NSW-based structural and civil engineering — design and certification.