The interior condition of the tenant’s usable square footage when it is without improvements or finishes. While existing improvements and finishes can be removed, thus returning space in an older building to its “shell” condition, the term most commonly refers to the condition of the usable square footage after completion of the building’s “shell” construction but prior to the build out of the tenant’s space. Shell construction typically denotes the floor, windows, walls and roof of an enclosed premises and may include some HVAC, electrical or plumbing improvements but not demising walls or interior space partitioning. In a new multi-tenant building, the common area improvements, such as lobbies, restrooms and exit corridors may also be included in the shell construction. With a newly constructed office building, there will often be a distinction between improvements above and below the ceiling grid. In a retail project, all or a portion of the floor slab is often installed along with the tenant improvements so as to better accommodate tenant specific under-floor plumbing requirements.