Can a BIC Legalise an Unauthorised Mezzanine Floor?

If you’ve discovered an unauthorised mezzanine floor in your commercial or industrial property, you’re not alone.It’s one of the most common compliance issues we see as town planning consultants in NSW.

The good news is that in many cases, a Building Information Certificate (BIC) can be used to regularise the unauthorised works.

But there are conditions, and it’s not always as simple as lodging a form with council.

Here’s what you need to know if you’re facing this issue, and how to handle it without triggering bigger planning headaches.

1. Understand what a BIC actually does

A Building Information Certificate is issued by your local council under the Environmental Planning and Assessment Act.

It confirms that the council will not take action for unlawful or unauthorised building works for seven years.

It is not a replacement for a development application (DA) or Complying Development Certificate (CDC).

Instead, it’s a tool within NSW planning to bring existing structures into compliance when no consent was obtained.

This makes it valuable when you’ve purchased or leased a building with unauthorised changes, like a mezzanine floor.

2. Councils expect evidence the mezzanine is safe and lawful in use

Just because a BIC can be issued doesn’t mean it always will.

Councils need to be satisfied that the structure is safe, structurally sound and lawful under planning controls.

For example, if your unauthorised mezzanine is used for office or storage in an industrial unit, it may be acceptable.

But if it’s being used for habitable purposes without proper fire safety or egress, the council may refuse the certificate.

As planning consultants, we review the site history, zoning and LEP controls to determine the risks early.

3. You’ll need clear architectural plans and inspections

One of the biggest delays in getting a BIC is lack of documentation.

If no plans exist, you’ll need to engage a professional for accurate measured drawings.

At Town Planning Sydney, our in-house drafting team prepares architectural plans that meet council and DA approval standards.

We also coordinate building inspections with private certifiers to ensure the mezzanine meets minimum NSW planning codes.

This reduces the chance of refusal or delays due to safety concerns.

4. Check if the mezzanine breaches planning controls

A mezzanine that takes the floor space over the allowable Floor Space Ratio (FSR) may not be eligible for a BIC.

Similarly, if the structure causes non-compliance with car parking, access or fire exits, council may ask for its removal.

We had a recent case in Western Sydney where a tenant installed a steel mezzanine in a warehouse without consent.

Council refused the BIC because the additional floor area created a fire hazard.

By redesigning the space and lodging a development application, we later secured council approval with the required upgrades.

Every site is different, which is why proper planning advice matters.

5. In some cases, a DA may be the better option

If the mezzanine was recently built or is causing safety or compliance issues, you may be better off lodging a DA.

This is especially true if the structure adds significant value or function to the premises.

A development application gives you the chance to justify the design, upgrade fire systems or seek concessions on planning controls.

In many cases, we use a two-step approach: apply for a DA to regularise the structure, then secure an Occupation Certificate.

This ensures the use is lawful and avoids complications down the track if you’re leasing or selling.

6. Engage a town planner early to avoid costly mistakes

Trying to lodge a BIC on your own often leads to delays, refusals or compliance notices.

Every NSW council has its own approach to these applications, and some are stricter than others.

As planning consultants, we deal with these issues every week and know what councils are likely to accept.

We help you gather the right documents, prepare proper architectural plans and liaise with certifiers and council staff.

This gives your application the best chance of success and avoids wasted time and money.

An unauthorised mezzanine doesn’t have to mean demolition or legal action.

With the right planning strategy, many can be legalised through a BIC or development application.

But it all depends on your site, structure and how you handle the process.

If you’re unsure what to do next, don’t guess, get proper planning advice first.