Category A vs Category B Fit Outs Explained
In short
A Category A fit out turns a shell into a basic, usable space with raised floors, ceilings, lighting, heating, cooling and toilets. A Category B fit out then tailors it to a specific occupier with partitions, meeting rooms, kitchens, branding, data and furniture. The landlord usually provides Cat A and the tenant Cat B.
Understanding Cat A vs Cat B fit out is essential when you are taking new commercial space, because it decides what you are paying the landlord for and what you will need to fund yourself. The terms are most common in offices, but the same principle applies to retail, clinics and other commercial premises.
Category A: a usable blank canvas
A Category A fit out sits between shell and core and a finished workplace. It typically includes:
- Raised access floors and suspended ceilings
- Basic lighting, usually to an open plan layout
- Heating, cooling and ventilation distributed across the floor
- Small power to floor boxes
- Toilets and showers
- Fire detection, alarms and emergency lighting to an open plan layout
- Finished internal surfaces in neutral decoration
Cat A is usually provided by the landlord to make a floor lettable. It is functional but not designed for any particular business.
Category B: making the space yours
A Category B fit out adapts the Cat A space to how the tenant works:
- Partitions, offices, meeting rooms and glazed screens
- Reception, breakout spaces, kitchens and tea points
- Feature lighting and ceilings
- Data, audio visual and security systems
- Adjustments to heating, cooling, ventilation, fire alarms and sprinklers to suit the new layout
- Flooring, joinery, branding and furniture
Cat B is usually funded by the tenant, sometimes helped by a contribution or rent free period from the landlord.
Which do you need?
If you are a landlord preparing a floor for the market, Cat A gives prospective tenants a clean, compliant space to picture themselves in. If you are a tenant taking a Cat A floor, your budget and programme should focus on Cat B. If you are taking space in shell and core condition, you will need both, and planning them together is usually the more efficient route.
Avoid paying twice
A common waste is installing Cat A finishes that are then ripped out for the tenant’s Cat B design: ceiling tiles removed for feature ceilings, lighting moved for meeting rooms, or floor boxes relocated. Where a tenant is agreed early, landlords and tenants often negotiate a Cat A Plus or straight to Cat B approach, with a contribution in place of works that would be removed.
Compliance in a Cat B fit out
New rooms change how a floor performs in a fire and how air moves. Partitions can block sprinklers, alter means of escape and travel distances, and need correct fire stopping where services pass through. Building regulations, the landlord’s fire strategy and the licence for alterations all need to be satisfied.
How we handle Cat A and Cat B projects at London’s Prestige
We deliver Category A, Category B and combined fit outs, coordinating design, landlord approvals, building control and every trade through one project manager. Where possible, we help clients plan the scope so nothing is installed twice. Learn more in our guide to commercial fit outs, see our commercial refurbishment service, and book a site visit to discuss your space.
Common questions
Who pays for a Cat A fit out?
Usually the landlord, to make the space lettable. The tenant usually pays for Cat B, sometimes with a contribution or rent free period from the landlord.
What is Cat A Plus?
A Cat A fit out with some extra features, such as a kitchen, meeting rooms or furniture, so a tenant can move in quickly without a full Cat B project.
Can I go straight from shell and core to Cat B?
Yes, and it often saves money by avoiding Cat A works that would be removed. It needs agreement with the landlord, often with a financial contribution in place of the Cat A works.