I have a fit out project which is occupying a new core and shell building. The scope of the core and shell includes wash room fitout on each floor and shower facilities in the basement for use by the whole building.

The tenant will be occupying the whole building and will be adding a gym, catering/ restaurant and kitchettes as part of the Fit Out works - this therefore includes adding a few WCs, Urinals and Wash Hand Basins, extra showers and faucets in the kitchettes and pre rinse spray valves in the kitchen areas.

To document WEp1 - should i calculate how many people might use the Fit Out WCs and Urinals and showers - based on the likely occupancy of those areas ? Otherwise my occupancy figure will be the same for WEp1 and WEc1 as they are occupying the whole building.
For the gym occupancy i could base this off the company's existing use and pro rata based on floor area. would this work if i provide a narrative to explain how the figures have been derived?

many thanks