The maze of commercial real estate jargon can often leave you perplexed, particularly when it comes to office fit outs. What exactly distinguishes a Cat A fit out from a Cat B, or what does the additional ‘A+’ signify in terms of practicality? Understanding these differences is crucial for businesses seeking an office space that suits their unique needs.

What is a Cat A fit out?

A Cat A (Category A) fit out refers to the level of finish applied to commercial spaces, making them suitable for potential tenants to customise according to their specific needs. This type of office fit out generally provides a basic level of finish, serving as a blank canvas for occupants to tailor the interior to their unique brand and operational requirements. The Cat A fit out covers the standards set within standard industry definitions, ensuring that the office spaces have the primary infrastructure in place for a business to operate.

Basic, ready-to-move-in office space

A Cat A fit out delivers office spaces that are ready to move in at a basic level. These are not personalised or branded but include the core fit and basic finishes needed to create an operable office space. Such spaces usually have finished internal wall surfaces, raised access floors, suspended ceilings, and a basic level of decoration. The space is typically considered a clean and empty space suitable for leasing, allowing for flexibility in designing the office layout by the incoming tenant.

What is a Cat B fit out?

A Cat B fit out is the next stage in transforming an office building’s interior space after a Cat A fit out has been completed. It takes the basic infrastructure into a finished office that reflects the identity and functional requirements of the incoming tenant. A Cat B fit out typically covers all the additional installations and decorative elements that create a comfortable, practical, and styled environment. This type of fit out caters to specific needs and preferences and includes:
  • Final floor finishes, such as carpet or hardwood flooring.
  • Customised partitioning for creating private offices, meeting rooms, and open-plan areas.
  • Bespoke electrical systems that suit the layout and functional needs of the organisation, including data cabling and personalised lighting solutions.
  • Mechanical services enhancements such as upgraded heating, ventilation, and air conditioning systems to match the tenant’s desired climate control.
  • Built-in furniture and workstations tailored to enhance the organisation’s productivity and space utilisation.
  • Soft furnishings and aesthetic decorations that align with the company’s branding and culture.
The Cat B fit out is essentially where the personalisation of the office space takes place, making the area fit for the intended use by the tenant.

Customised option

Opting for a Cat B fit out means that a company has the opportunity to customise an office space according to its own specifications and brand identity. This level of personalisation allows the tenant to influence the office layout, ensuring that they are getting a space that is designed specifically for their work style and company culture. Features like colour schemes, type of office furniture, and the inclusion of branding elements become a critical part of this phase.

The Cat B fit out is often regarded as presenting a ‘move-in ready’ office space for the tenant. This level of finish means that the office is fully functional for the staff immediately upon completion, eliminating the need for additional work before the space can be used.

The following table summarises the key aspects of Cat B fit outs:

FlooringCarpet, hardwood, or other specific finishes
PartitioningBespoke design in line with the layout
ElectricalCustomised lighting and power to match company use
HVACUpgraded systems for optimum climate control
FurnitureErgonomic and design-centric, unique to the tenant
DecorBrand-aligned aesthetics and colours
IT & TelecommunicationsState-of-the-art systems for seamless connectivity
FixturesHigh-quality and special-purpose fittings and finishes

It is paramount that the process caters to the detailed demands of the tenant while also being practical and in alignment with the lease agreement. Since the upfront costs of a Cat B fit out are substantial, this affords the tenant the ability to weigh the benefits of custom design features and their effect on workplace efficiency and employee well-being against these costs.

Main differences between Cat A and Cat B fit outs?

When exploring the various types of office fit outs, it’s essential to differentiate between Cat A and Cat B, as they serve unique purposes and are tailored to distinct phases in the preparation of office spaces. Here are the main differences:
  • Blank Canvas vs. Detailed Customisation: Cat A fit outs are akin to a blank canvas, providing basic finishes and mechanical and electrical services that establish a functional but generic office building. Alternatively, Cat B fit outs take this canvas and transform it into a detailed painting, customising the space with a company’s brand identity, practical design features, and a variety of soft furnishings and internal layouts.
  • Structural Essentials vs. Aesthetic Specifics: With a Cat A fit out, the emphasis is on secondary fit out works such as creating concrete floors with a basic finish, implementing standard industry definition air conditioning units, and ensuring the presence of fire protection systems and electrical services. Conversely, a Cat B fit out progresses to finer details such as specific office layout, office spaces, breakout areas, and includes aesthetic considerations like colour schemes and high-quality materials.
  • General Functionality vs. Business Functionality: Cat A provides a general functionality that could suit any business with minimal design, offering things like raised access floors and suspended ceilings but leaving room for the tenant’s input. Cat B delves into the personal needs of a business, focusing on space planning, departmental positioning, technological installations specific to business operations, and integrating the company’s ethos into the design.
  • Economic Outlay and Timing: Understanding upfront costs is crucial too. Cat A fit outs involve standard build-out costs and are typically completed before a lease agreement is signed. In contrast, a Cat B fit out involves more complex budgeting, as the level of finish, type of fit, and inclusion of bespoke elements must be taken into account and are often negotiated during or after the lease agreement is set.

What factors should businesses consider when choosing between Cat A and Cat B fit outs?

When it comes to renovating or moving into a new office building, businesses must weigh various factors before deciding on the type of office fit out that best suits their needs. The decision between a Cat A and Cat B fit out revolves around various aspects, such as budget constraints, the extent of customisation desired, and the branding requirements.

Making an informed choice is crucial because each fit out type offers different benefits, and the right selection can result in a workspace that not only serves operational needs but also aligns with the company’s ethos and client impressions. Factors such as the upfront costs, expected lease term, and the company’s growth projections also play significant roles in the decision-making process.


Understanding the financial implications of a Cat A versus a Cat B office fit out is fundamental for businesses. A Cat A fit out may seem less expensive upfront because it involves bringing an office space to a standard industry definition of basic finishes—which includes essential services such as protection systems, air conditioning, and access floors, without any elaborate internal finishes.

On the other hand, a Cat B fit out is more tenant-specific, incorporating the design and complete build out of office spaces, including all the internal finishes, soft furnishings, and any company-specific structural changes. Although the initial costs are higher, a Cat B fit out means the business moves into a fully designed, customised space that requires no further building works. Depending on the lease agreement details, landlords may sometimes contribute towards the Cat B fit out, effectively reducing the tenant’s upfront expenditure.

What is a Cat A+ fit out?

A Cat A+ fit out represents a hybrid of Cat A and Cat B fit outs, offering a more advanced level of finish than Cat A but not as customised as Cat B. This type of fit out is ideal for businesses looking for a quicker move-in time with some degree of personalisation without the extensive work involved in a full Cat B fit out.

Enhanced, move-in ready office space

A Cat A+ fit out delivers a more polished and functional space compared to a Cat A fit out. It includes elements that make the office space immediately usable with minimal additional work required by the tenant. Typical features of a Cat A+ fit out include:
  • Finished ceilings and floors that go beyond the basic specifications of Cat A.
  • Partitioned spaces such as meeting rooms and private offices, ready for use.
  • Installed lighting and power outlets, ensuring that the office is fully operational from day one.
  • Basic furniture like desks and chairs, providing an initial setup for the incoming tenant.

Key features of a Cat A+ fit out

Cat A+ fit outs are designed to bridge the gap between the standard, empty office space of Cat A and the highly customised environment of Cat B. They offer a level of convenience and readiness that appeals to businesses needing a functional workspace quickly. Key features often include:
  • Intermediate finishes: Higher quality finishes than Cat A, such as better flooring and ceiling options.
  • Partitioned areas: Pre-built meeting rooms, offices, and breakout areas.
  • Lighting and power: Fully installed lighting systems and power outlets, designed to be ready for immediate use.
  • Basic furnishings: Inclusion of essential furniture like desks, chairs, and storage units.
  • Functional infrastructure: Ready-to-use mechanical and electrical systems, ensuring a comfortable working environment.

Benefits of a Cat A+ fit out

Choosing a Cat A+ fit out can provide several advantages for businesses:
  • Speed: Faster move-in time compared to a full Cat B fit out.
  • Cost-effective: Less expensive than a fully customised Cat B fit out, offering a balanced solution.
  • Flexibility: Allows for some level of personalisation while providing the essential elements needed for immediate occupancy.
  • Convenience: Ready-to-use space with basic furnishings and infrastructure, reducing the need for additional work before starting operations.
By opting for a Cat A+ fit out, businesses can enjoy a well-equipped office space that requires minimal setup, enabling them to focus on their core activities without the delays and costs associated with more extensive fit outs.

Office Fit Out Guide

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