A Guide to a Cat A and Cat B Office Fit Out

Jeremy Poole

An office fit out is essential to create a foundation for a functional and aesthetically pleasing workspace that aligns with your company’s needs and culture. However, when it comes to deciding what level of fit out you require, industry jargon can be complicated, and it can be difficult to establish your needs.

Generally, there are two main types of office fit out: Cat A and Cat B. These terms are used to specify the classification of fit out you need, and also helps to differentiate between the elements needed for each type of fit out.

As well as these primary categories, there are also other options to be aware of, such as shell and core, and Cat A+ fit outs. In this blog, we will explore the key distinctions between each category of office fit out, and highlight their key aspects to help you make an informed decision for your office space transformation.

What are the different categories of office fit out?

As we’ve mentioned Cat A and Cat B fit outs are already widely known when it comes to an office fit out. However, there are four classifications of office fit out in total. These include:

  • Shell and Core
  • Cat A
  • Cat B
  • Cat A+

What is a Shell and Core Office Fit-Out?

A Shell and Core office fit out is something that occurs before a Cat A or Cat B fit out. Put simply, this classification of fit out involves adapting and renewing the infrastructure of a space in preparation for an office build. The name ‘Shell and Core’ essentially describes the state of your office space before any fundamental features are installed such as lighting and flooring.

With a Shell and Core fit out, tenants will be responsible for fitting out the space. This could involve designing and constructing the interior partitions, installing electrical systems, lighting, flooring, interior walls, ceilings, and other  necessary features to support their business operations.

Whilst this kind of office space can look finished from the outside, the inside space will not yet be useable.

What is a Cat A Office Fit Out?

A Cat A, or category A, office fit out refers to a basic level of office development, typically undertaken in a commercial building by a property developer or landlord.

The primary purpose of a Cat A fit-out is to provide a blank canvas for incoming tenants that will allow them to envision their ideal workspace. This means they can customise the space according to their needs once they have moved in.

Although the specific definition of a Cat A office fit-out can vary from from one company to another, the fit out generally includes standard features that are essential elements required for occupancy.

What are the key features of a Cat A office fit out?

Fundamental Features: A Cat A fit-out will have essential building services already installed, such as electrics, heating, ventilation systems, fire detection, and basic lighting. These services are brought up to a functional standard that will be suitable for any tenant, but will lack any personalisation.

Raised Access Flooring: Cat A fit outs will also include raised access flooring to facilitate the installation and maintenance of cables and wires throughout the office space.

Suspended Ceilings: To conceal services and improve acoustic performance, suspended ceilings are also commonly installed as part of Cat A fit outs.

Base Building Finishes: In terms of design, a Cat A fit out will provide a basic level of finish to the office space. This may include plain walls and basic floor coverings. Though this mightn’t sound exciting, it will allow tenants to envision their own design concepts without being constrained by existing decoration.

What is a Cat B Office Fit Out?

On the other hand, a Cat B fit out occurs after the tenant has secured the lease and its purpose is to customise the space to suit the specific requirements and branding of the business. This level of office fit out focuses much more on the interior design and customisation aspect of the office space, which should be tailored to the tenant’s functional and aesthetic preferences.

At this point, most businesses will consider hiring an office design and build company to design, manage, and install their new office.

What are the key features of a Cat B office fit out?

Customisation: A Cat B fit out involves designing and creating the internal office layout, including meeting rooms, breakout areas, workstations, and executive offices. This layout can be designed completely bespoke to the needs of the business and should accommodate daily tasks and employee working styles.

Partitioning and Joinery: Internal walls, partitioning, and bespoke joinery are all features installed during a Cat B fit-out to create private spaces and storage solutions as required.

Furniture and Fixtures: Cat B fit outs also involve the selection and installation of office furniture, fittings, and fixtures that reflect the company’s brand identity, and will help to create a cohesive office environment.

Technology and AV Installations: From advanced IT infrastructure to audio-visual systems for presentations and video conferencing, Cat B office fit outs should cater to the businesses technology requirements.

Finishes and Branding: Arguably the most exciting part, a Cat B fit out also allows businesses to include decorative elements such as wall finishes, floor coverings, and branding elements to help showcase their corporate identity to both employees and customers.

What is a Cat A+ Fit Out?

A Cat A+ office fit out is a design concept that falls between a Cat A and Cat B fit out. Put simply, a Cat A+ fit out is minimal in design like a Cat A fit out, but features such as technology solutions, partitioning and joinery fixtures, and meeting rooms will already come pre-fitted when a tenant moves in. These existing design features will mean that a Cat A+ office space will be ready for occupancy immediately.

The main benefit of this is that the occupant will need to make minimal adjustments to the space once they have moved in. Additionally, this will also keep any upfront costs for the tenant reasonably low. This classification of office fit out is valuable for

those businesses who need an office space quickly, and potentially on a short-term basis, where major changes are not necessary.

Cat A vs Cat B office fit out, which is better?

Now that you have all this information, you’ll need to decide which classification of fit out you require.

The main difference between a Cat A and a Cat B office fit out lies in their scope and purpose. A Cat A layout is ideal for companies that like to work with a completely blank canvas. If your company is moving from an old office space, then you’ll be able to use most of your existing furnishings and fittings to re-design the space. Alternatively, a Cat B layout is best for businesses that would like to completely transform their brand identity in a new space. A Cat B office fit out will allow you to customise the space bespoke to your brand, and will ensure the layout fits your requirements.

However, if you find neither of these option sound quite right for your business, then a Cat A+ fit could be the perfect solution for you. Cat A+ fit outs are a fantastic option for businesses who want to keep their costs low. Further, if you’re only going to be using your office on a temporary basis, a Cat A+ fit out requires minimal effort during the moving and design process.

Get in touch

At Building Interiors, we can assist you with your Cat A, Cat B, or Cat A+ fit outs. If you’d like to discuss this with a member of our team, you can drop us an email at contact@buildinginteriorsgroup.co.uk or call us on 0113 388 6522.