‘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.That Work needed to complete the internal layout and servicing of the building shell to meet the specific needs of an incoming occupier. The building shell is the structural and non-structural envelope of a building provided as a primary stage (usually for a speculative developer) for a subsequent project to fit out with internal accommodation works.