Office fit out: the ultimate guide

What is an office fit out and what does it include?

An office fit out is the transformation of an office shell into a functional workplace that’s fit for occupation and aligned with the needs of its end-users. Depending on the overall scope of the project, an office fit out can cover everything from layout planning and partitioning to raising floors, installing core facilities and shaping internal spaces, such as kitchens, collaboration zones and meeting rooms. Furniture, technology, lighting, acoustics and finishes all fall within the reach and remit of an office fit out.

As we explain below, fit outs fall into different categories indicating different levels of development, from Shell & Core to Cat A and Cat B interventions. An office fit out differs from a refurbishment in that it involves the installation of start-from-scratch facilities and the transformation of empty space. A refurb, on the other hand, involves repairs, upgrades and improvements to pre-existing elements and already functioning workspace.  

The key stages of an office fit out

An office fit out typically follows a clear sequential workflow that goes from initial brief to fully operational workplace. Within this journey, key fit out stages tend to cluster into seven core phases, as follows:

1/ Workplace consultancy & project brief: understanding business objectives, headcount, workflows, budgets and timelines; defines the functional and strategic requirements that drive later decisions.

2/ Site surveys & feasibility assessments: measuring and assessing structural, mechanical, electrical and compliance constraints; confirms what is achievable within a set budget and programme.

3/ Concept design & space planning: developing layouts, test-fits, mood boards, 3D visuals, furniture strategy, finishes and sustainability considerations; aligns the design with operational needs through iterative refinement.

4/ Costing, proposals & approvals: pricing of labour, materials, building controls and third-party costs, seeking of landlord approvals and safety sign-off; confirms project scope, budget and compliance.

5/ Procurement & preconstruction: ordering materials and furniture, scheduling suppliers and health and safety planning; helps to coordinate lead times and logistics.

6/ Onsite construction & delivery: partitioning, flooring, M&E installation, decoration, IT/AV integration and furniture installation; managed through structured project coordination.

7/ Handover & post-occupancy: delivering final compliance documentation, snagging and final close out of minor defects; helps to ensure smooth occupation and end-user experience.

Types of Office Fit Out

It total there are three main types of office fit out, which together encompass the full range of stages and services involved in workspace creation. The most common categories, and those we cover in this article, are known as Cat A and Cat B.

The other main category is Shell & Core (or Base Build), which refers to the outer and inner framework of a building. While at this stage a building may look complete from the outside, inside it will be empty. A Shell & Core fit out may deliver communal features, such as lifts, lobbies, stairwells and reception areas, but otherwise occupiers will be greeted with bare floors and exposed services.

There’s also a category known as Cat A+, which sits somewhere between Cat A and Cat B. Referred to as the ‘plug and play’ option, Cat A+ is essentially a Cat A fit out, only with greater levels of functionality and finish.

Cat A fit out

A Cat A fit out is a basic operational fit out that leaves the interior of a building empty, providing you with an unfurnished but functional office space. Focused on the installation of key infrastructure, a Cat A fit out will include mechanical, electrical and plumbing services, plus suspended ceilings, flooring and fire detection systems. It builds on the framework of Shell & Core, with a view to readying office space for corporate occupancy.

The Cat A fit out process is typically undertaken by a landlord as part of preparing their premises for commercial occupation. Once the space has been delivered, the incoming business takes possession and will usually carry out a Cat B fit out (see below), adding tailored interior elements to shape the space into a fully operational and branded work environment.

Key features of a Cat A fit out include:

• Air conditioning
• Toilets
• Basic lighting
• Railed access flooring
• Gridular ceilings
• Basic fire detection systems
• Data networks
• A building management system
• Hot and cold water feeds

Cat B fit out

A Cat B fit out refers to the stage where a landlord‑delivered, functional shell is transformed into a fully tailored working environment. Building on the foundations established during a Cat A fit out, Cat B introduces the design language, furnishings and operational elements that complete the space and make it ready for day‑to‑day business use.

Beyond installing the components that make a workplace practical, a Cat B fit out is also where an organisation’s identity comes to life. It’s the moment the space becomes recognisably yours, shaped around your brand, culture and ways of working.

Whereas Cat A fit outs are typically delivered by the landlord, Cat B fit outs are usually undertaken by the tenant in partnership with an architect, design studio or specialist fit out contractor. At this stage, every design decision – from layout to finishes to furniture – is tailored precisely to the operational needs and identity of your business.

Key features of a Cat B fit out include:

• Partitions
• Meeting rooms
• Offices
• Breakout zones
• Storage
• Reception areas
• Kitchen areas
• Tea points
• Cabinets & workstations

The Cat B process also includes the selection and procurement of desks, chairs and other office furniture, plus interior finishes such as artwork, decorative lighting, wall hangings, biophilia and corporate branding.

How will an office fit out benefit your business?

An office fit out can strengthen your business by turning functional space into a strategic asset. A well‑designed environment improves workflow, supports hybrid collaboration and enhances employee wellbeing through better acoustics, lighting, ergonomics and ambiance. It also sharpens your brand presence, giving clients and partners a clear sense of who you are the moment they walk in. By aligning layout, technology and amenities with how your teams actually operate, a well-delivered fit out can help to boost productivity and attract and retain talent. Ultimately, it creates a workplace that feels purposeful and ready to support your organisation’s growth.

The benefits of a Cat A fit out:

• Provides a ‘blank canvas’ on which new tenants can express themselves
• Lays the foundations for a company to create new workspace tailored to its needs an ambitions
• Guarantees a functional, practical and presentable base for your business

The benefits of a Cat B fit out:

• Creates your own space designed specifically around the needs of your people and business
• Provides a workspace that’s tailored to your ways of working
• Ensures all features and areas are customised to enhance productivity and reflect your organisation’s brand values

How to define your needs

When it comes to defining the needs of your organisation, planning is critical. It’s generally advised that you should start planning at least 18 months in advance of your move. This will enable you to develop a project timeline and create an effective workplace strategy, ensuring you don’t rush into crucial decisions.

You then need to create an insightful brief, which underpins any successful office move and fit out. A brief will help you identify your key objectives, such as:

• Business change (rebrand, expansion, consolidation, merger)
• Staff retention and recruitment
• New lease
• Reduced costs and overheads
• Increased visibility
• Introduction of new ways of working
• Uplift in employee engagement, motivation and productivity

You also need to distinguish between your workplace (building) and workspace (interior work environment). By looking into these elements, you will gain a clear understanding of needs and issues associated with your new office, which will help you shape decisions and prioritise actions.

For example, regarding your workplace:

• Are your building and local area good fits for your brand?
• How far is your building from key suppliers?
• Is your building located close to transport hubs and amenities?
• What are the local commuting routes and options?
• Will local businesses be complementary or competitors?

And in terms of your workspace:

• Do you expect to expand or contract in the next five years?
• Does your work environment support employee performance and productivity?
• What sort of space planning is required to support your business requirements?
• How can you leverage new space to get the best from your people?

When do you need an office fit out?

The first big decision you need to make is whether you should move office and engage in the fit out process, or stay put and refurbish your existing space.

The decision whether to stay or go, to relocate or renegotiate, is a crucial one. To make this decision, you need to ask yourself a few key questions. For example, due to market changes since you signed your lease, are there alternative properties worth exploring? Do you need to move to support your growth ambitions? Or could your current office be reimagined and refurbished to create the space you need?

Ultimately, the decision will come down to whether or not your current office is fit for purpose and meets your requirements as a business. If the answer’s no, it’s time for an office move and fit out.

Once you’ve identified the need to move, there are a few things to consider:

• Start your search as soon as you can; the sooner your start, the greater your chances of identifying the new space you want. Remember, it can take three months to research new properties and up to three months to negotiate a lease. So the sooner you start the better.
• Engage a property agent to help find your new space. A good agent will understand shifting market dynamics and can support you in your negotiations with landlords.

The cost of an office fit out

There is no definitive cost for an office fit out. But there are a range of cost-related elements to consider, such as the size and location of your project and specific workplace requirements. The following information is based on a typical 10,000 sq ft project in London.

Cost per sq ft (typical)

Type of cost	Low	Mid	High
Construction	£70	£90	£120
Furniture	£20	£35	£60
AV & IT	£5	£10	£15
Dilapidations	£15	£18	£20
Security	£1	£2	£3
Total	£111	£155	£218

How to finance an office fit out

For any organisation, an office relocation and fit out require substantial investment. From design and architecture fees to security, IT, tech and relocation expenses, there’s a range of big, small and unexpected costs along the way.

Luckily, there are number of financing options available to you. Typically, office fit out financing blends capital, asset finance and leasing, with businesses drawing on cash reserves, loan financing and sale-leaseback mechanisms to fund their projects.

Remember, you don’t have to purchase your fit out assets outright. In the UK, many firms spread costs over 12 to 60 months through hire purchase or finance leases, preserving cash flow while accessing tax benefits.[JC1]  Indeed, in many instances costs linked to office fit outs qualify for tax deductions to help minimise the overall financial impact.

If you need guidance on fit out financing, our expert advisers are here to help. Contact WRKPLC on XXX for more information.

How to calculate your budget

To calculate your fit out budget, you need to consider the range of variables that could affect your final costs. As a general rule, it’s recommended to budget a year’s rent towards your office fit out costs. 

Key areas of potential expenditure include:

Building

• Maintenance
• Rent
• Rates
• Stamp duty
• Running contracts
• Service charges
• Building security
• Existing space dilapidations

Capital expenditure

• Fit out & furniture costs
• New AV systems, installation and training
• Telephone lines
• IT infrastructure and hardware

Advisory

• Legal
• Cost consultancy
• Environmental audits
• Commercial property agency

Logistics

• Relocation management
• Mail redirection
• PR and marketing

Other

• Project continency
• Insurance
• Staff training

Who is involved in the fit out process?

An office fit out brings together a coordinated group: an internal project leader who sets direction and manages decisions; a wider internal team who define functional needs and operational priorities; and a finance team who validate budgets, approvals and commercial viability.

In addition, you’ll need to engage various external consultants. Commercial agents advise on suitability, lease terms and negotiation. Technology consultants define IT, AV and infrastructure requirements. Legal teams manage contracts and compliance, plus landlord obligations. And workplace specialists translate organisational needs into spatial design and cultural expression.

Together, these key stakeholders help to shape a fit out process that aligns with your business requirements and ensures that unforeseen costs, risks and challenges are identified and addressed.

You’ll also need to meet with your prospective landlord, who will oversee building standards and compliance. Open and honest dialogue with your landlord can go a long way to ensuring a smooth fit-out process and positive workplace occupancy.

H3: How to choose your fit out partner

Finding the right office design & build company for your project is no easy task. In the UK, there are a range of designers, architects, workplace specialists and consultants to choose from.

To help guide your selection, here are some key partner qualities and characteristics to look out for:

• Technical knowledge: understanding of contemporary methods and materials to deliver the workspace you desire.
• Creativity: creative ways of meeting your brief to deliver unique workplace solutions.
• Attention to detail: rigorous approach to work and exceptionally high standards to minimise problems and delays.
• Track record: reputation, awards, accreditation and case studies to demonstrate their ability to deliver.
• Sustainability credentials: strong eco commitments to ensure your project has a positive impact on the planet; can be demonstrated through certifications such as ISO 14001 and Planet Mark.
• Wide-ranging expertise: ability to help out on every project element.
• Wellbeing focus: accreditations, such as ISO 45001, WELL and Fitwel, will demonstrate dedication to employee wellbeing.
• Budget brain: ability to deliver projects on time and to budget.

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