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By Adam Murphy, Principal Building Designer at ANS Design

Understanding Unauthorized Building Works in NSW — and How ANS Design Can Assist with a Building Information Certificate (BIC)

Building or renovating without the correct approvals is more common than many homeowners realise. In New South Wales, unauthorized works can range from garage conversions and enclosed patios to large extensions, secondary dwellings, decks, pergolas, carports, and internal alterations completed without council approval or certification.

Sometimes the works were completed years ago by a previous owner. In other cases, homeowners may have relied on incorrect advice, assumed approval was not required, or started construction before obtaining the necessary Development Application (DA), Complying Development Certificate (CDC), or Construction Certificate (CC).

Regardless of how it happened, unauthorized building works can create significant issues when:

• Selling a property
• Refinancing with a bank
• Applying for future approvals
• Dealing with council complaints
• Responding to neighbor concerns
• Obtaining occupation or compliance documentation
• Addressing insurance or legal matters

At ANS Design we regularly assist property owners throughout Sydney and NSW with preliminary assessments, council liaison, design documentation, and support relating to Building Information Certificate (BIC) applications for existing unauthorized works.

What Is Considered “Building Without Approval”?

In NSW, most building works require approval under either:

• A Development Application (DA)
• A Complying Development Certificate (CDC)
• A Construction Certificate (CC)
• Or another applicable approval pathway

Examples of works commonly found to be unauthorized include:

• Garage conversions into habitable rooms
• Secondary dwellings or granny flats
• Patio and pergola enclosures
• Carports exceeding exempt limits
• Structural alterations
• Additions to existing homes
• Retaining walls and drainage works
• Internal reconfiguration affecting fire safety or structure
• Decks, awnings, and enclosed outdoor areas
• Commercial fit-outs or building alterations

Even if the works appear professionally built, approval is still generally required.

What Can Happen If Building Works Are Unauthorized?

1. Council Investigation or Compliance Action

If council becomes aware of unauthorised works, they may investigate the property and request documentation relating to approvals, plans, and certification.

This may occur due to:

• Neighbor complaints
• Property sale investigations
• New DA or CDC applications
• Routine council inspections
• Swimming pool compliance checks
• Stormwater or drainage complaints

Council may issue:

• Requests for Information
• Notices of Intention
• Orders to cease use
• Orders to demolish or rectify works
• Penalty infringement notices (fines)

The outcome generally depends on the severity of the issue, planning compliance, safety concerns, and whether the works are capable of being regularized.

2. Difficulties Selling the Property

Unauthorised works are often identified during conveyancing or purchaser due diligence.

Buyers may discover:

• No approval history exists
• Floor plans do not match council records
• Structures were added without approval
• Occupied spaces are non-compliant

This can result in:

• Reduced property value
• Delayed settlement
• Purchasers withdrawing
• Requests for retrospective approvals
• Banks refusing finance approval

Many property owners only become aware of approval issues when preparing to sell.

3. Problems with Insurance or Liability

Insurance providers may investigate whether works were legally approved following storm, fire, structural, or injury-related claims.

Unauthorized works can potentially create complications regarding:

• Structural liability
• Fire safety
• Waterproofing
• Occupancy classification
• Building compliance

This is especially important for converted garages, habitable rooms, secondary dwellings, and structures built near boundaries.

4. Future Renovations Become More Difficult

Existing unauthorised works can complicate future:

• Development Applications
• CDC approvals
• Construction Certificates
• Subdivision proposals
• Renovations or additions

Council or certifiers may require the existing issues to be addressed before new approvals can proceed.

What Is a Building Information Certificate (BIC)?

A Building Information Certificate (BIC) is an application made to the Local Government Authority (Council) under the Environmental Planning and Assessment Act 1979.

A BIC does not automatically “approve” illegal works in the same way as a DA or CDC. However, if granted, it generally prevents council from taking demolition or alteration action against the subject building for a specified period, provided the works remain substantially unchanged.

A BIC application is commonly used where building works already exist and retrospective assessment is required.

Can Any Unauthorized Works Be Approved Through a BIC?

Not always.

Council will generally assess matters such as:

• Structural adequacy
• Building Code compliance
• Fire safety
• Health and amenity impacts
• Drainage and stormwater
• Setbacks and planning controls
• Privacy and overlooking
• Site coverage and building height
• Whether the works are reasonably acceptable

Some works may require:

• Rectification works
• Additional reports or certifications
• Fire upgrades
• Engineering documentation
• Amended building works

In some situations, parts of the works may not be supportable and removal may be required.

This is why obtaining professional advice early is extremely important.

How ANS Design Can Assist

At ANS Design we assist homeowners by assessing the likely approval pathway and preparing the documentation often required to support a Building Information Certificate application.

Our Assistance May Include:

Preliminary Site Inspection & Assessment

We can inspect the property and review:

• Existing site conditions
• The extent of unauthorized works
• Available approval history
• Potential planning or compliance concerns
• Whether the works may be supportable

This early-stage assessment is often critical before investing further time and consultant costs.

Council & Consultant Coordination

ANS Design can assist with:

• Liaison with council
• Coordination with certifiers
• Discussions with consultants
• Identifying likely documentation requirements
• Clarifying potential approval pathways

Depending on the project, additional consultants may also be required, including:

• Structural engineers
• Building surveyors
• Fire consultants
• Hydraulic consultants
• Surveyors

Preparation of Plans & Documentation

Where appropriate, we can prepare:

• Existing condition plans
• As-built drawings
• Site plans
• Floor plans and elevations
• Compliance documentation
• Planning justification information
• Design amendments where required

Clear and professional documentation is essential when dealing with retrospective approval matters.

Identifying Potential Compliance Issues Early

One of the biggest advantages of engaging a professional building designer early is identifying potential issues before formal submission.

This may include reviewing:

• Ceiling heights
• Natural light and ventilation
• Setbacks
• Site coverage
• Drainage concerns
• Fire separation requirements
• Structural considerations
• Habitable room compliance

Early identification can help reduce delays, redesign costs, and unnecessary consultant expenses.

Common Projects We Assist With

ANS Design regularly assists with projects involving:

• Garage conversions
• Secondary dwellings / granny flats
• Carports and patio structures
• Alterations and additions
• Enclosed outdoor entertaining areas
• Existing residential additions
• Retrospective approval investigations
• Preliminary compliance assessments

Important Things Property Owners Should Know

Every Property Is Different

There is no “one size fits all” outcome for unauthorized works.

The success of a BIC application depends on:

• The type of works completed
• Site constraints
• Applicable planning controls
• Building compliance matters
• Council assessment outcomes
• The quality of supporting documentation

Early Advice Can Save Significant Money

Attempting to resolve approval issues without professional guidance can often lead to:

• Incorrect applications
• Delays
• Additional consultant costs
• Repeated council requests for information
• Avoidable rectification works

Obtaining an early assessment can help clarify the likely pathway before major costs are incurred.

Need Assistance With Existing Unauthorized Works?

If you have existing building works completed without approval — or are unsure whether previous works were properly approved —  ANS Design can assist with preliminary advice, site inspections, design documentation, and guidance relating to potential Building Information Certificate application pathways throughout Sydney and NSW.

Whether the issue involves a garage conversion, secondary dwelling, carport, extension, or other existing works, obtaining professional advice early can help you better understand your options and reduce potential risks moving forward.

For assistance with retrospective approval investigations, BIC-related documentation, or preliminary site assessments, contact ANS Design to discuss your project requirements.

About the Author

Adam Murphy
Principal Building Designer
ANS Design, Sydney NSW

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