If you’re looking to move into a new office or refurbish your existing premises, you may feel slightly overwhelmed with the jargon that we take for granted in the world of construction. We’re here to answer your questions and decode the jargon so that you can get the most out of your project.

What is fit out?

This is the end-to-end process of making an internal space suitable for occupation. It’s the transformation of a concrete shell into a working space; from installing facilities (like the the loo!) and raising the flooring, to installing team breakout areas, meeting rooms and workstations.

As the tenant, it’s important that you confirm with your landlord or developer what level of finish they’ll provide. Often a space will be provided by the landlord or developer as either a Shell and Core or a Cat A fit out, leaving it up to the tenants to provide the final working finish in what is known as a Cat B fit out.  

There is no standard industry definition of each of these, so we’ll take you through what you can broadly expect to see during each of these stages.  We’d always recommend confirming with your landlord or fit out specialist what will be included during contract negotiation. 

What is a Shell and Core? 

A Shell and Core is the basic internal framework of the building that has been completed. At this point an office building will look complete from the outside, however the space will simply be an empty shell on the inside. If a developer is planning to hand over a project in this state, it is unlikely you’d have any level of polished finish, so expect to see concrete floors and exposed ceilings. A Shell and Core fit out may have shared areas completed, for example; the building reception, lifts and communal toilets, however it’s best to check this with your developer. 

What is Cat A or Category A fit out?

A Cat A fit out will provide a basic level of finish. This may include raised floors, suspended ceilings and internal surfaces, along with basic mechanical and electrical services. While Cat A spaces will have a floor and walls, they'll be quite basic and finished to an industrial standard.

It’s also worth bearing in mind that a landlord may request for the space to be returned back to them in Cat A condition at the end of the tenancy.

What’s usually included in a Category A fit out:

  • Raised floors and suspended ceilings (with a basic finish)
  • Basic mechanical and electrical services
  • Fire detection services and smoke alarms
  • Air-conditioning and ventilation (HVAC)
  • Basic internal finishes 

What is Cat B or Category B fit out?

Cat B fit out provides you with a workspace in a finished condition that's ready for your staff to move into. At this point, tenants will often work with office designers, property consultants and architects to determine how the space can be used to maximise productivity for the client and boost their bottom line.

A Cat B fit out tends to include interior partitions to divide up the space and create offices, meeting rooms and breakout spaces. At this stage, you’ll also choose the final finish for the floors, walls and doors (including textures and colours) to reflect your corporate culture and branding. Cat B also covers the planning and installation of IT infrastructure, ensuring enough power outlets and AV facilities are available to support your working style.

Finally, workstations and furniture are selected and installed, getting the space ready for staff to move into.

What’s usually included in a Category B fit out:

  • Fully fitted kitchens and non-communal office amenities
  • Partitioning; including meeting rooms, offices and breakout spaces
  • Workstations and furniture
  • Reconfiguring air-conditioning and power points
  • IT installation and infrastructure
  • Design and brand detailing

Is a refurbishment the same as a Cat B fit out?

The terms refurbishment and fit out are often used interchangeably, however a refurbishment refers specifically to an existing office space that’s being re-done. A refurbishment project may include the stripping out an existing Cat B fit out before replacing it with a new and improved Cat B that works better for the new tenant.

If you’re moving to a new development it’s most likely that you’ll be leasing either a Shell and Core or Cat A space and so this wouldn’t be classed as a refurbishment. If you’re renovating your existing office space, then this would be classed as a Cat B refurbishment.


It’s worth bearing in mind that while basic flooring and services (such as mechanical and electrical services) will be installed in a Cat A fit out, they may need to be moved to suit the design and layout chosen in a Cat B fit out. To avoid installing then removing these core components, it’s often worthwhile having your Cat A and Cat B fit outs delivered by the same contractors.

If you need any more help or advice at any stage of your office fit out project, feel free to get in touch.

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