Engineering Design Certification in Australia: Form 15, Regulation 126 and NCC Compliance

Engineering design certification plays an important role in Australian construction. It provides professional evidence that a building element, structure or building-services system has been designed and assessed against the applicable technical and regulatory requirements.

In New Zealand, this type of documentation is commonly associated with a PS1 Producer Statement – Design. Australia does not use PS1 and PS4 producer statements as a national certification system.

Instead, Australian engineering certification varies between states and territories. Depending on the project location, certification may involve engineering calculations, certified drawings, design certificates, inspection records and prescribed state-specific forms.

In Queensland, one of the most commonly requested documents is a Form 15 Compliance Certificate for Building Design or Specification.

Understanding the Australian engineering certification process can help architects, builders, fabricators, developers and property owners prepare the correct documentation and avoid unnecessary delays during building approval and construction.

What Is Engineering Design Certification?

Engineering design certification is written confirmation from an appropriately qualified professional that a building design, specification or structural element has been assessed against the applicable technical requirements.

Certification may relate to an entire structural system or an individual building element, such as:

• Balustrades

• Glass barriers

• Structural steelwork

• Aluminium structures

• Beams and columns

• Footings and foundations

• Retaining walls

• Canopies and awnings

• Pergolas

• Carports

• Louvre roofs

• Privacy screens

• Mechanical equipment supports

• Seismic restraint systems

• Building-service supports

The certification package will generally identify what has been designed, the information relied upon and any limitations applying to the design.

Is There an Australian Equivalent to a PS1?

Australia does not have one direct national equivalent to New Zealand’s PS1.

A New Zealand PS1 is a standardised producer statement relating to engineering design. In Australia, the terminology and documentation differ according to the state or territory in which the work is being completed.

Australian engineering design documentation may include:

• A professional engineer’s certificate

• A structural design certificate

• Certified engineering drawings

• Structural calculations

• A design compliance statement

• A state-prescribed certificate

• A technical engineering report

• Evidence of suitability for an NCC solution

In Queensland, a Form 15 often performs a similar practical function to a New Zealand PS1 because it certifies a building design or specification.

However, the documents are not identical, and a Form 15 should not simply be described as an Australian PS1.

What Is a Queensland Form 15?

A Queensland Form 15 is a compliance certificate relating to a building design or specification.

It may be issued by a person who is appropriately qualified to certify the particular aspect of the design covered by the certificate.

For structural work, this will commonly be a suitably qualified professional engineer.

A Form 15 may identify:

• The building or project

• The aspect of the design being certified

• The drawings and documents reviewed

• The relevant building assessment provisions

• The standards used in the design

• The extent of the certification

• Design conditions or limitations

• The certifier’s qualifications and registration details

The Form 15 is generally provided to the appointed building certifier as part of the building approval documentation.

When Is a Form 15 Required?

A Form 15 may be requested where a building certifier requires professional certification for a particular building design or specification.

Common examples include:

• A custom balustrade design

• A glass pool barrier

• An aluminium louvre roof

• A structural canopy

• A carport or veranda

• Structural steel connections

• A retaining wall

• A support frame for mechanical equipment

• Seismic restraint of building services

• A proprietary product used outside its generic limitations

• A modification to an existing structure

Not every building element automatically requires a Form 15.

The need for certification depends on factors such as:

• The type of work

• The building classification

• The approval pathway

• The complexity of the design

• The location of the project

• Whether a standard or proprietary solution is available

• The requirements of the building certifier

The required documentation should be confirmed with the building certifier before fabrication or construction begins.

Form 15 and the National Construction Code

The National Construction Code, commonly known as the NCC, establishes the minimum technical requirements for building and plumbing work throughout Australia.

The NCC is a performance-based code. Compliance may be achieved using:

• A Deemed-to-Satisfy Solution

• A Performance Solution

• A combination of both

Assessment methods used to demonstrate compliance can include evidence of suitability, Verification Methods, comparison with Deemed-to-Satisfy Provisions and Expert Judgement.

A professional engineer’s certificate may form part of the evidence used to demonstrate that a material, design or form of construction is suitable for its intended purpose.

A Form 15 therefore supports the NCC compliance and building approval process by documenting the engineer’s assessment of a particular design or specification.

What Does an Engineer Review Before Certification?

Before providing engineering design certification, the engineer may review:

• Architectural drawings

• Structural drawings

• Fabrication drawings

• Product specifications

• Material grades

• Member sizes

• Connection details

• Supporting structures

• Site conditions

• Wind classification

• Equipment weights

• Building classification

• Intended use

• Relevant Australian Standards

• NCC requirements

The engineer may also prepare calculations to verify that the proposed design can safely resist the applicable loads.

Certification should only cover the design information that the engineer has reviewed.

What Is Included in an Engineering Certification Package?

An engineering certification package may include more than the certificate itself.

Depending on the project, the package may contain:

• Form 15 or another design certificate

• Structural calculations

• Certified engineering drawings

• Connection details

• Anchor specifications

• Material requirements

• Post-spacing schedules

• Glass schedules

• Design loads

• Installation notes

• Design assumptions

• Certification limitations

The certificate should be read together with the referenced drawings and calculations.

A Form 15 without the supporting documents may not provide enough information for fabrication or installation.

Certified Engineering Drawings

Certified engineering drawings communicate the design requirements to builders, fabricators and installers.

They may show:

• Member sizes

• Material grades

• Post spacing

• Connection layouts

• Weld sizes

• Bolt sizes

• Anchor types

• Fixing quantities

• Footing dimensions

• Reinforcement

• Support locations

• Installation requirements

The drawings should clearly identify any conditions that must be satisfied for the certification to remain valid.

If the project changes after certification, the revised design should be referred back to the engineer.

Structural Engineering Calculations

Structural calculations provide the technical basis for the certified design.

Calculations may consider:

• Dead loads

• Live loads

• Wind actions

• Earthquake actions

• Equipment loads

• Impact loads

• Member strength

• Deflection

• Connection capacity

• Anchor capacity

• Footing capacity

• Supporting structural capacity

The amount of calculation detail required will depend on the complexity and risk associated with the building element.

The building certifier may request calculations in addition to the design certificate and drawings.

Site-Specific and Generic Engineering Certification

Engineering designs may be either site-specific or generic.

Site-specific engineering

A site-specific design is prepared for a particular project, address and set of conditions.

It may consider:

• Project dimensions

• Site wind classification

• Building height

• Terrain and exposure

• Supporting structure

• Material selections

• Connection details

• Installation arrangement

Site-specific certification is commonly required for custom or complex structures.

Generic engineering

A generic design may cover a product across a defined range of:

• Sizes

• Spans

• Heights

• Wind classifications

• Materials

• Post spacings

• Fixing arrangements

• Support conditions

A generic certificate is only applicable where the proposed installation remains within every stated limitation.

If the project falls outside those limits, a site-specific engineering assessment may be required.

Engineering Certification for Balustrades

Balustrades and fall protection barriers are common examples of building elements requiring engineering design and certification.

A balustrade engineering assessment may review:

• Barrier height

• Post spacing

• Top-rail capacity

• Infill capacity

• Glass thickness

• Bracket strength

• Anchor capacity

• Supporting slab or framing

• Wind loads

• Barrier loads

• Openings and climbability

The certified drawings may also specify whether the balustrade is top-mounted, face-mounted, fixed to concrete or connected to structural framing.

Any change to the post spacing, glass size, fixing type or supporting structure should be reviewed by the engineer.

Engineering Certification for Louvre Roofs and Pergolas

Louvre roofs, pergolas, patio roofs and similar outdoor structures may require engineering certification where they are subject to significant wind or structural loads.

The engineer may assess:

• Beams

• Posts

• Louvre blades

• Rafters

• Bracing

• Footings

• Building connections

• Wind uplift

• Roof loads

• Drainage loads

An attached structure may also transfer additional loads into the existing building.

The existing roof, walls or foundations may need to be assessed before the structure can be certified.

Engineering Certification for Canopies and Awnings

Canopies and awnings can experience substantial wind uplift, particularly when they are cantilevered or installed at height.

Certification may cover:

• Structural framing

• Supporting rods

• Cantilevered beams

• Glass or roof panels

• Brackets

• Welds

• Bolts

• Anchors

• Connections to the existing building

The connection to the supporting structure is often one of the most important parts of the design.

A canopy frame may have adequate strength but still be unsafe if it is fixed to unsuitable cladding, masonry or lightweight framing.

Engineering Certification for Mechanical Equipment Supports

Mechanical equipment may require structural design and certification for its supports and fixings.

This may include:

• Air-conditioning units

• Air-handling units

• Fans

• Pumps

• Chillers

• Condensers

• Ductwork

• Pipework

• Mechanical platforms

• Rooftop plant

The engineer may consider equipment weight, vibration, operating loads, wind actions and earthquake restraint.

The supporting slab, steelwork, roof framing or wall must also be capable of carrying the transferred forces.

Seismic Restraint Engineering Certification

Seismic restraint certification may be required for non-structural building components such as:

• Mechanical equipment

• Ductwork

• Pipework

• Cable trays

• Electrical equipment

• Suspended services

• Storage systems

• Architectural components

The design may include:

• Bracing rods

• Steel brackets

• Restraint cables

• Support frames

• Anchors

• Flexible connections

• Direct structural fixings

Seismic certification should identify the equipment covered, support arrangement, anchor requirements and applicable design limitations.

Form 15 Versus Construction Certification

A Form 15 generally relates to the design or specification of a building element.

It does not automatically confirm that the work was constructed correctly.

After installation, separate evidence may be required to confirm that the completed work matches the certified design.

This may involve:

• A site inspection

• Construction photographs

• Installer records

• Fabrication records

• As-built measurements

• Anchor installation records

• Product certificates

• A prescribed inspection or construction certificate

The specific certificate required after construction depends on the project, person carrying out the inspection and Queensland building certification requirements.

Is a Form 15 the Same as a Form 16?

No. A Form 15 and Form 16 serve different purposes within Queensland’s building certification framework.

A Form 15 relates to a building design or specification.

A Form 16 may be used in certain circumstances to document the inspection of an aspect of building work.

However, the correct post-construction certificate depends on who performed the work or inspection, their qualifications and the type of building work involved.

The building certifier should confirm which construction or inspection certificate is required.

Does a Form 15 Approve the Building Work?

A Form 15 does not, by itself, constitute building approval.

It is supporting documentation provided to the building certifier.

The building certifier remains responsible for:

• Assessing the building application

• Reviewing the submitted documentation

• Determining whether the proposed work complies

• Establishing inspection requirements

• Issuing the relevant building approval or permit

A building certifier may accept an engineer’s certificate as evidence for a particular aspect of the design, but the certifier remains responsible for the overall approval process.

Can Council Issue a Form 15?

A Form 15 is generally issued by the appropriately qualified person responsible for certifying the relevant design or specification.

For structural engineering work, this will commonly be a professional engineer rather than the local council.

The form may then be submitted to a private building certifier or council building certifier as part of the approval process.

The approval authority may review the certificate and supporting information before deciding whether it is acceptable.

Who Can Provide Engineering Certification?

The person providing engineering certification must have suitable qualifications and experience for the aspect being certified.

For professional engineering services in Queensland, registration requirements may also apply.

The engineer should have appropriate competence in the relevant field, which may include:

• Structural engineering

• Civil engineering

• Mechanical engineering

• Electrical engineering

• Fire engineering

• Hydraulic engineering

A person should not certify work outside their qualifications, experience or professional area of competence.

Does Engineering Certification Guarantee Approval?

Engineering certification can support a building application, but it does not guarantee that approval will be issued.

The building certifier may request:

• Additional calculations

• Revised drawings

• Further product evidence

• Clarification of the design scope

• Site-specific information

• Additional professional certifications

• Changes to address NCC or planning requirements

Preparing a complete and coordinated engineering package can reduce the likelihood of delays.

What Information Does an Engineer Need?

To prepare a design and certification, the engineer may request:

• Project address

• Architectural drawings

• Relevant plans and elevations

• Building classification

• Product drawings

• Fabrication details

• Material specifications

• Member dimensions

• Equipment weights

• Proposed fixings

• Supporting structure information

• Site photographs

• Wind classification

• Soil information

• Building-certifier requirements

Providing complete information at the beginning of the project generally reduces revisions and certification delays.

Changes After Engineering Certification

A certified design should not be changed without review where the alteration could affect structural capacity or compliance.

Changes requiring engineering review may include:

• Increasing spans

• Increasing post spacing

• Reducing member sizes

• Changing material grades

• Substituting anchors

• Changing bracket dimensions

• Altering support conditions

• Moving equipment

• Changing glass thickness

• Modifying welds

• Fixing into a different substrate

Even minor-looking changes can alter the load path and invalidate the original design assumptions.

Engineering Inspections

An engineering inspection may be required to verify that critical elements have been installed in accordance with the certified drawings.

The engineer may inspect:

• Member dimensions

• Structural connections

• Welds

• Bolts

• Anchors

• Reinforcement

• Footings

• Post spacing

• Glass details

• Brackets

• Support conditions

Critical or concealed elements should be inspected before they are covered.

Where an engineer cannot attend the site, they may request photographs and supporting records, although the appropriate evidence will depend on the work and certification requirements.

Retrospective Engineering Certification

Retrospective certification may be requested where a building element has already been constructed without appropriate engineering documentation.

This can be more difficult than certifying a design before construction because important details may be concealed.

The engineer may require:

• Site measurements

• Destructive investigation

• Concrete scanning

• Anchor testing

• Material verification

• Construction photographs

• Original drawings

• Product information

• Exposure of concealed connections

Retrospective certification cannot always be provided if there is insufficient evidence to verify the design and construction.

Early engineering involvement is therefore preferable.

Evidence of Suitability and NCC Documentation

The NCC requires building materials, products, forms of construction and designs to be fit for their intended purpose.

Evidence used to demonstrate suitability may include certificates, engineering reports, calculations, testing documentation and other supporting information.

A certificate from a professional engineer or another appropriately qualified person is one form of evidence that may be accepted to support NCC compliance.

However, the evidence must be appropriate for the particular material, product, design or form of construction being assessed.

Why Early Engineering Certification Matters

Engaging an engineer early can help the project team:

• Confirm whether certification is required

• Identify applicable standards

• Develop practical connection details

• Confirm member sizes

• Assess the supporting structure

• Select suitable anchors

• Coordinate fabrication

• Establish inspection requirements

• Avoid non-compliant construction

• Reduce costly redesign

Waiting until fabrication or installation is complete can make compliance more difficult and expensive to demonstrate.

Engineering Certification Across Australia

Engineering certification requirements are not identical across Australia.

Each state and territory has its own:

• Building legislation

• Professional registration requirements

• Certification terminology

• Prescribed forms

• Building approval procedures

• Inspection requirements

The NCC provides national technical requirements, but it is given legal effect through state and territory building and planning laws.

For projects outside Queensland, the relevant local certification and registration requirements should be confirmed before design work begins.

Frequently Asked Questions

What is the Australian version of a PS1?

There is no single national Australian version of a PS1. In Queensland, a Form 15 design certificate may serve a similar practical purpose for a specific building design or specification.

Is a Form 15 required for every structural element?

No. The need for a Form 15 depends on the building work, approval pathway and building-certifier requirements.

Does a Form 15 include structural calculations?

The form itself is the certification document. Structural calculations and certified drawings may be supplied as supporting documentation.

Can a builder issue a Form 15?

A Form 15 must be issued by a person appropriately qualified to certify the relevant design or specification. Structural designs will commonly be certified by a suitably qualified engineer.

Does a Form 15 confirm the work was installed correctly?

No. A Form 15 relates to the design or specification. Separate inspection or construction evidence may be required after installation.

Can a generic Form 15 be used on several projects?

Potentially, but only where every project falls within the conditions and limitations of the certified generic design. Otherwise, site-specific certification may be required.

Is engineering certification the same throughout Australia?

No. Certification requirements, forms and professional registration rules differ between states and territories.

Supporting Safe and Compliant Australian Construction

Engineering design certification helps demonstrate that building elements have been properly designed and assessed against applicable technical requirements.

Although Australia does not use New Zealand’s PS1 system nationally, similar evidence is provided through certified engineering drawings, calculations, professional certificates and state-specific documentation such as Queensland’s Form 15.

By engaging qualified engineers early, confirming building-certifier requirements and following the certified design during construction, project stakeholders can reduce compliance risks and deliver structures that are safe, durable and suitable for their intended use.