Request a callback from the Rap Interiors team

0333 600 1234

Email us

Close form


For the most part, you can leave the construction jargon to the industry professionals. However, sometimes you need to understand the lingo to identify what you need and what to expect from your chosen fit out contractor.

Office fit outs are a prime example. For both landlords and tenants, it’s important to understand the difference between a CAT A and CAT B office fit out, as the two are very different.

If you have reached a point where you are confused by the fit out jargon, then this blog’s aim is to help you understand it. In simple terms, we break down the office fit out terminology so you can commence your project with confidence.

So, without further ado, read on to learn the difference between a CAT A and CAT B fit out.

Let’s Start with Shell and Core

At the early stage of an office fit out, the building’s exterior will look complete, but the interior will typically consist of concrete floors and walls and no lighting or facilities. In short, you will see the basic internal framework of the building as presented by the developer.

While the main office space(s) will be in a “bare bones” state, developers often finish the communal areas to a high standard.  These may include lifts, toilets and the reception; i.e. the areas that all the building’s occupiers can use.

What is a CAT A Fit Out?

Once a landlord has invested in the space, they will conduct a CAT A (short for “category A”) office fit out before putting the property to market to find a tenant. This generally includes work to the flooring, ceiling, fire and safety facilities, mechanical and electrical services, air-con and ventilation, basic internal finishes and more depending on the space.

Following CAT A work, the space is essentially takes the form of an empty, open plan “blank canvas”. There are no desks and chairs, decorations or meeting rooms, as these elements are left to the incoming tenant for the next phase of the fit out – the CAT B.

What is a CAT B Fit Out?

Once the landlord finds a tenant, the Category B fit out phase begins. Tenants oversee and fund this part of the work, as they need to tailor the space to suit their unique needs and working practices. In addition to making the space suitable for the incoming workforce, tenants will play a big part in developing the aesthetic so it reflects their company identity and branding.

Usually, the tenant will consult the help of an office fit out company to develop the space design and, later, conduct the install of the new elements. These may include, but are not limited to, the following:

  • Office furniture solutions – Common furniture solutions include shared and individual desks, task chairs, height adjustable desks, soft furnishings, meeting tables, pods and booths.
  • Meeting rooms – Partitioning will be required to create private meeting rooms. These are essential for collaboration, Zoom chats and meetings where employees share sensitive information.
  • Decorations and Branding – These are key in making the space look inviting and creating a brand experience. Many companies introduce bespoke glass manifestation, feature walls and decorative acoustic panels.

Other elements covered by CAT B include breakout areas, finishes, kitchen areas, ICT solutions and power points. Once the tenant is happy with the makeup of the space, the office is ready to move into.

Related Content: Office Design Trends and Ideas 2022

How About CAT A+?

The CAT A to CAT B model typically requires tenants to sign a fixed, long-term contract. However, in the current market, many tenants are seeking shorter-term contracts that offer more flexibility. This has resulted in landlords offering an alternative to the CAT A to CAT B model, known as CAT A+.

The CAT A+ model is simply where landlords offer pre-fitted, fully furnished spaces to tenants on a shorter term deal. The spaces are connected to Wi-Fi, allowing tenants to easily plug in their devices and work away. This is why many people refer to these spaces as “plug and play” offices.

Simply put, tenants get a fully functional workspace without having to commit for the long term, which is particularly attractive to small, ambitious businesses.

Related content: What is a CAT A+ Office Fit Out?

Is an Office Refurbishment the Same as an Interior Fit Out?

Not exactly. An office refurbishment comes later down the line when the space is occupied. There are a number of reasons for a workplace refurbishment, such as a company re-brand, spatial changes to accommodate more or less employees, or simply the need to freshen things up.

It is also worth noting that, upon leaving a space, tenants are often required to fund restoration work at the request of the landlord. This is called an office dilapidation, which you can learn about here.

In a Nutshell

To summarise, a CAT A fit out is the basic finishing of the building’s interior. It is commissioned by the landlord in order to create a “blank canvas” ready to put to market to find a tenant.

The incoming tenant conducts the CAT B fit out. At this stage, the office interior design is tailored to the tenant’s unique needs and aesthetic preferences. This includes furniture, decorations, space planning, branding, finishes and breakout spaces.

Thank You for Reading!

If you have been struggling with the fit out terminology, then we hope this blog has helped to demystify the jargon. Ultimately, it is a smart idea to learn some of the lingo before embarking on a new project, and by reading this article, you have already made a good start!

Are You in Need of an Office Fit Out Company?

With over 30 years’ experience, Rap Interiors has established itself as one of the leading office fit out companies in London and the UK. Whether you are looking to carry out a CAT A or CAT B fit out, Rap’s dedicated team of designers, estimators, project managers and skilled tradespeople can help you to achieve your goals.

To speak to a member of our friendly client care team, call 0333 600 1234 or fill out the form below.


Related Content