Cat A vs Cat B Office Fit-Out: What Tenants Should Know

Cat A and Cat B are two stages of fitting out an office. Cat A is the basic finish of the space, usually delivered by the landlord: floors, ceilings, lighting, air handling and essential services. Cat B is the tenant's stage, where the empty floor becomes your workplace with rooms, furniture, IT, branding and the kitchen. The split sounds simple, but the exact line moves from building to building, and that is where tenants lose money and weeks. This guide explains both categories, shows who normally does what, and gives you a checklist for Slovenian office leases.

TL;DR

• Cat A is the base finish above shell and core: raised floors, suspended ceilings, basic walls, electrics, lighting, HVAC, basic plumbing connections and fire detection.
• Cat B is the tenant's customization: partitions, meeting rooms, kitchens, furniture, joinery, branding, IT, AV and security.
• The conventional split is landlord for Cat A and tenant for Cat B, but there is no industry-standard definition, so the lease must list inclusions item by item.
• Budget and programme for Cat B separately from rent, and agree handover condition and end-of-lease reinstatement before you sign.
• In Slovenia, put the delivery condition of the premises in the contract. A landlord who fails to deliver it can be held to account, but a clear schedule prevents the dispute.

Table of Contents

• What Cat A and Cat B mean
• Cat A vs Cat B at a glance
• What a Cat A fit-out typically includes
• What a Cat B fit-out includes
• Who is responsible for what
• The real cost question: budget Cat B before you sign
• Which one should you choose?
• Handover and end-of-lease: where disputes start
• A checklist for viewing an office
• How we can help
• FAQ
• Sources

What Cat A and Cat B mean

The terms come from the British and Irish office market and are now used by international developers and occupiers, including in Ljubljana's newer office buildings. They describe how far a space has been completed at the moment you receive it and what remains to be done.

A building is usually described in three layers:

1. Shell and core. The structure, facade, stairs, lifts, risers and toilets cores. Nothing inside the floor plate is finished.
2. Cat A. The floor plate is made usable as generic office space.
3. Cat B. The space is designed and built for one specific occupier.

According to Turner & Townsend's 2026 fit-out cost guide methodology, Category A is the basic on-floor finish above shell and core. It covers raised access floors, suspended ceilings, basic painted walls, electrical distribution, lighting, HVAC, basic plumbing connections and fire detection with smoke alarms. The same methodology defines Category B as a finished space that can be moved into immediately, normally designed and installed for the tenant and aligned with its brand and workforce needs.

In plain terms: a Cat A floor is an empty, serviced canvas. A Cat B floor is an office where people can sit down and work on Monday.

Cat A vs Cat B at a glance

The table is a conventional picture. Chawner & Trench describe Cat A as the baseline infrastructure and essential services the landlord provides so the space is ready for occupation, and Cat B as customizing the workspace to the tenant's operational, branding and design needs.

What a Cat A fit-out typically includes

Cat A is about making the building's services reach the floor and giving it a neutral finish. Based on the Turner & Townsend definition, expect:

• Raised access floors that allow power and data to run underneath.
• Suspended ceilings that conceal services.
• Basic painted walls around the perimeter and core.
• Electrical distribution and lighting at a standard specification for open-plan use.
• HVAC that conditions the floor, often laid out for a generic density of people.
• Basic plumbing connections to the core.
• Fire detection and smoke alarms.

What you do not get is a place to put a team: no meeting rooms, no kitchen, no furniture, no cabling to your desks and no brand.

The in-between: Cat A+

Some landlords now offer an enhanced stage between the two, often called Cat A+ or plug-and-play. The landlord goes further, so the space is ready to occupy with limited tenant work. If a listing mentions it, treat the name as a marketing label and ask for the specification list, because what sits inside varies from one building to the next.

What a Cat B fit-out includes

Cat B completes the workplace on top of the Cat A base. Turner & Townsend list the typical elements as:

• internal partitions and doors
• wall and floor finishes
• upgraded ceilings
• specialist or decorative lighting
• cafés, tea points and kitchens
• built-in and loose furniture
• bespoke joinery
• decoration and branded materials
• IT infrastructure and AV
• security equipment
• upgrades to the Cat A services

That last item matters. If you split an open floor into twelve rooms, the air conditioning, sprinklers or detection laid out for an open plan may need to be modified. These changes are part of your Cat B scope and budget, and they often need the landlord's consent for work on building systems.

Who is responsible for what

The usual convention: the developer delivers shell and core, the landlord delivers Cat A, and the tenant delivers Cat B. But the fit-out firm Overbury points out that there is no industry-standard definition of shell and core, Cat A or Cat B, and advises confirming the inclusions with the landlord or a fit-out specialist during contract negotiation. That is the most practical sentence in this whole topic. Two buildings can both advertise "Cat A" and hand over very different spaces.

What Slovenian law says about delivery condition

Slovenian commercial leases have long been shaped by the business premises act, the ZPSPP, which was valid until 18 June 2021. For leases governed by it, the legal analysis by Dida Volk states that the landlord had to deliver the premises fit for the purpose stated in the contract and maintain them in that condition. If the landlord does not deliver the premises in the contractually required condition, the tenant may withdraw or arrange the premises after first giving the landlord a reasonable period, and may also claim damages.

The practical lesson holds for any lease you sign today: the contract defines the "purpose" and the "condition". If the lease only says "office space" and does not say Cat A, ceilings, HVAC capacity or power per desk, you have little to measure the landlord against. Have a lawyer confirm which rules apply to your particular lease, since your contract and the legislation in force at signing decide.

The real cost question: budget Cat B before you sign

Rent is only part of what moving costs. Cat B is a project, and it needs its own budget, design time and construction programme. Three things drive it:

1. Layout intensity. A mostly open-plan office with a small kitchen is far cheaper than one with many closed rooms, acoustic treatment and a client-facing reception.
2. Specification level. Specialist lighting, bespoke joinery and premium finishes raise the cost quickly.
3. Technology. IT infrastructure, AV for meeting rooms and security systems are line items on their own.

Turner & Townsend publish a global office fit-out cost guide that benchmarks these costs by city, which is useful for a first sense of scale. For a Slovenian office, get quotes from a designer or fit-out contractor against your actual plan, because the benchmark cannot see your layout.

Time is a cost too

Cat B takes time between receiving the keys and moving people in: design, permits where needed, procurement, build, cabling and testing. If your current lease ends in three months, a Cat A space may not be the right choice, however attractive the rent looks. A space already fitted out, or one delivered at an enhanced standard, can shorten the path. Ask early whether the landlord grants a rent-free period for the fit-out. That is a negotiating point, not a rule, and the lease should state it if agreed. Our practical guide to commercial lease negotiation in Slovenia covers where tenants have room to push.

Which one should you choose?

Choose a Cat A space if:

• you have a strong brand or specific workflow and want a layout designed around it
• you plan to stay long enough to recoup the investment
• you have the time for a design and build stage
• the landlord is offering a contribution or a rent-free period toward your works

Choose an already fitted or enhanced space if:

• you need to move quickly
• your team is small and the needs are standard
• you prefer predictable costs
• the lease is shorter or you expect to change size soon

Choose Cat B delivered by the landlord (a turnkey arrangement) if:

• you want one party responsible for the result
• the landlord is willing to build to your specification and price it into the rent or a separate agreement

Whichever you pick, a lease should state who does the fit-out, to what specification, who owns what is installed, and what happens at the end.

Handover and end-of-lease: where disputes start

The condition of the premises on handover and at exit is where Slovenian disputes tend to arise. A recent example reported in the media is the former UniCredit premises at Wolfova 1 in Ljubljana, where, according to Nova24TV, the landlord is seeking restoration costs after the tenant left and the parties disagree about the condition of the premises. You do not need a high-profile building for the same issue to appear: every Cat B fit-out you build can become a reinstatement obligation.

Before signing, settle these points in writing:

• Handover specification. A schedule listing Cat A items: floor type, ceiling height, HVAC capacity, power per square meter, lighting level, fire detection, toilets, lift access.
• Photos and a handover protocol recording the condition on the day you receive the keys.
• Consent for works. What you may change without approval, and what needs the landlord's sign-off, especially for HVAC, sprinklers and facade.
• Reinstatement. Whether you must remove partitions and cabling at exit, restore the Cat A condition, or may leave improvements in place.
• Ownership of fixed items such as joinery, kitchens and cabling.
• Fit-out period. The date rent starts relative to the date you get access.

If you are thinking about how a lease ends, our article on commercial lease termination options in Slovenia is a useful companion. A bank guarantee is another common security item, and it often interacts with reinstatement claims, so read both together.

A checklist for viewing an office

When a broker says a space is "Cat A", ask these questions on site:

1. Is there a written specification of the Cat A works, and is it attached to the lease?
2. What is the floor-to-ceiling height after the ceiling and raised floor?
3. How many people is the HVAC designed for, and how are zones controlled?
4. How much electrical capacity is available on the floor, and where are the connection points?
5. Where are the toilets and risers, and can a kitchen connect to water and waste?
6. What are the fire strategy constraints on partitions and exits?
7. What building rules govern contractors, working hours and deliveries?
8. What does the landlord offer toward the fit-out: contribution, rent-free period or an enhanced finish?

You can also use our letter of intent guide to lock key fit-out terms before the full lease is drafted.

Perspective

In our experience, tenants rarely get into trouble because Cat B is expensive. They get into trouble because nobody wrote down where Cat A ends. A label on a listing is not a specification, and the most useful thing a tenant can do is turn the label into a list of items.

That is why we treat the fit-out question as part of the lease strategy, not an afterthought. When we represent a tenant, we look at the space, the landlord's delivery scope, the timeline and the exit terms together, and we negotiate them as one package. When we represent a landlord, we help define a clear Cat A specification so that the space is easier to let and less likely to end in a disagreement about condition.

Our approach is boutique and personal: we stay involved from the market search and analysis through negotiation to the signed transaction, and our knowledge of the Slovenian and regional commercial market is the base for that advice.

Maruša

How we can help

If you are looking for an office and want the fit-out terms to be clear before you sign, we can represent you as a tenant, from the search and analysis to the negotiation and the close. Landlords can work with us on presenting and leasing their space with a defined delivery standard. See our office rental in Ljubljana page or the wider commercial spaces we work with, or contact us through hoof.si to talk through your requirements.

For owners with existing buildings, our property management and valuation and market analysis services help you decide whether to upgrade a space to a higher delivery standard before letting it.

FAQ

What does Cat B fit-out mean?

A Cat B fit-out is the second stage, in which the tenant turns a basic Cat A space into a working office. It typically includes partitions, meeting rooms, kitchens or tea points, finishes, furniture, joinery, branding, IT, AV and security. It is designed around the tenant's own needs.

Is Cat A or Cat B paid by the tenant?

Conventionally the landlord delivers Cat A and the tenant delivers Cat B. In practice the lease decides, and some landlords offer a contribution, a rent-free period or an enhanced finish. Put the split in writing, item by item.

What is the difference between Cat A and Cat B in an office?

A Cat A office has a basic level of finish and essential services, with a neutral, open space. A Cat B office is tailored to the tenant, adding rooms, finishes, furniture, IT and AV, kitchens, branding and upgrades to services.

Is there a standard definition of Cat A?

No. Fit-out specialists note that shell and core, Cat A and Cat B have no industry-standard definition. Always ask for the specification list of what the landlord delivers, and have it attached to the lease.

Who should I ask if I am unsure what a Slovenian lease requires?

Ask a lawyer experienced in commercial leases to review the delivery condition, fit-out consent and reinstatement clauses, and ask a commercial real estate agent to confirm what the market offers. Both questions are cheaper to settle before signing than after.

Sources

• Methodology, Global office fit-out cost guide 2026, Turner & Townsend
• Cat A vs Cat B Fit-Out: What's the Difference?, Chawner & Trench
• What is the difference between Cat A and Cat B fit out, Overbury
• Zakon o poslovnih stavbah in poslovnih prostorih (ZPSPP), PISRS
• Dida Volk: Najemna razmerja za poslovne prostore, Tax-Fin-Lex
• UniCreditova zapuščina na Wolfovi 1, Nova24TV

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• Traditional Office or Coworking? What Are Companies Really Looking for Today?
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• Tenant Improvement Allowance in Slovenia: How It Works