The Difference Between a ‘Shell & Core’, ‘CAT A’ & ‘CAT B’ Fit-Out

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The Difference Between a ‘Shell & Core’, ‘CAT A’ & ‘CAT B’ Fit-Out

Fit-out’ is a term used to describe the process of making interior spaces suitable for occupation. It is often used in relation to office developments, where the base construction is completed by the developer, and the final fit-out by the occupant. The occupant will generally be leasing space as a tenant from the developer / landlord.

Depending on the degree of completion of the building, and the interior specification required by the occupant, fit-outs can take a range of different forms such as ‘Shell & Core’, ‘CAT A’ or ‘CAT B’.

It can be confusing for those that are not familiar with the industry jargon , so here are an explanation of each of the terms:

Shell and Core:                                             

It covers the essentials that can be installed before your fit-out partner can tailor the office space for your needs. It generally comprise the structure, cladding, base plant, completed common areas and external works.

The key communal areas will include:

Once this phase is completed you’re left with the bare bones, or the basic ‘shell’.

Category A Fit-Out:

mezzanineThere is no standard industry definition for a Category A fit-out, generally this is carried out for developers and landlords to turn the space into a blank canvas. Generally this will include:

The developer will often make a contribution to the tenant for the carpets, floor boxes and towards the CAT B fit-out .

Category B Fit-Out:

CAT B fit outCategory B, is where all bespoke design elements will be worked on and installed, so the company can add their own stamp on the place and reflect their brand identity.

This will include installation of:

These categories do not have standard definitions, and so it is very important that contract documentation sets out precisely what work is to be carried out and by who, rather than relying on ambiguous short-hand terms.

If you are looking into an office refurbishment or fit out please feel free to contact Crown Interiors. We can offer advice and a wealth of experience on both Cat A and Cat B developments.