By QED Consulting Engineers — structural & civil engineers, Notting Hill, Melbourne
A mezzanine is a raised floor built inside an existing building to make use of the space above — for offices, storage or extra work area. Its structure of columns, beams and decking must be designed by a structural engineer for the intended load, and it usually needs a building permit. Here's what's involved.
What is a mezzanine floor?
A mezzanine is an intermediate floor that doesn't reach the full height of the building, adding usable area without extending the building's footprint. They're common in warehouses, retail fitouts and industrial buildings where there's unused vertical space.
Loads and structure
The first question is what the mezzanine will be used for, because that sets the design load — office and light storage are very different from heavy pallet storage. The engineer designs the columns, beams and floor decking to carry that load safely, along with the bracing that keeps the structure stable. Under-designing a mezzanine is dangerous; the load rating has to match the real use.
Permits and compliance
A mezzanine is building work, so it generally needs a building permit, with structural documentation and compliance with the NCC. Depending on its size and use, requirements around access, egress and fire may also apply. Your building surveyor confirms what's needed.
Fixing to the existing structure
A mezzanine usually sits within an existing building, so the engineer checks how it connects to — or stands independently of — the existing structure and slab. The existing floor slab has to be able to carry the new column loads, or the footings are designed accordingly.
Our commercial and industrial engineering team designs mezzanines for warehouses and fitouts across Melbourne.
Adding a mezzanine? Talk to a Melbourne structural engineer for a compliant, load-rated design.
Frequently asked questions
Do I need a permit for a mezzanine? Usually, yes — a mezzanine is building work that generally requires a building permit and structural documentation. Your building surveyor confirms the requirements.
How much load can a mezzanine hold? That's set by its design — the engineer designs the mezzanine for the intended use, whether office, light storage or heavy storage. The load rating must match the actual use.
Do I need an engineer for a mezzanine? Yes — the columns, beams, decking and connections all require structural design for the intended load and for the permit.
How is a mezzanine fixed to an existing building? The engineer designs the connections and checks that the existing slab or new footings can carry the column loads.
