Cat A vs Cat B Fit-Out: Who Pays for What
Cat A is the landlord's base finish — a blank, serviced but unusable floor with ceiling, lighting, basic HVAC and raised floor. Cat B is the tenant's build on top of it: the layout, cabins, meeting rooms, branding and everything that makes the space specific to one occupier.
By Dhruv Agarwal · · 2 min read
Why it matters on a fit-out project
This is where fit-out budgets go wrong before design even starts. A tenant sees a completed Cat A floor — ceiling in, lights on, air conditioning running — and reasonably assumes most of the work is done.
It is not. Cat A is deliberately generic, and Cat B frequently involves undoing part of it. Understanding the split early is what stops a budget being set against the wrong scope.
What sits in each
| Element | Cat A (landlord) | Cat B (tenant) |
|---|---|---|
| Raised access floor | Usually provided, bare | Floor finish, boxes, outlets |
| Ceiling | Grid and tiles, open plan | Cut, adapted or replaced for the layout |
| Lighting | Uniform general lighting | Zoned, feature and task lighting |
| HVAC | Distribution to the floor | Rebalanced and rerouted to the layout |
| Fire systems | Sprinklers, detection, open plan | Relocated to suit rooms and cabins |
| Partitions | None | All cabins, meeting rooms, glazing |
| Power / data | Basic distribution, incoming | Small power, containment, AV, IT |
| Finishes | Sealed floor, painted core | Carpet, wall finishes, joinery, branding |
| Furniture | None | All |
Common mistakes
- Budgeting Cat B on a Cat A impression. The floor looks finished, so the scope gets underestimated by exactly the value of everything above.
- Not scheduling Cat A in the lease. "Warm shell" means different things to different landlords. It should be an annexed schedule, not a term.
- Ignoring what Cat B undoes. Sprinkler relocation, ceiling adaptation and HVAC rebalancing are real line items in every cabinised layout.
- Fixing the layout before compliance is checked. Adding rooms changes escape routes, travel distance and occupancy under NBC 2016 Part 4 — cheap to solve on a drawing, expensive after ceilings close.
- Comparing quotes across different scopes. One contractor pricing Cat B only against another pricing Cat A adaptation plus Cat B is not a comparison.
Standards referenced
Occupancy, exits and travel distance — all of which move when a Cat A floor is subdivided into a Cat B layout — are governed by NBC 2016, Part 4.
Standards referenced
- NBC 2016, Part 4 — Fire and life safety — occupancy