Dear All,

 
One of our clients is developing an expansion to an existing airport.

The scope of this expansion includes an area of new WCs (around 550 m2), sized to satisfy the needs of the expected occupancy for this expansion zone. However, accesses to the expansion zone can be done via the existing building with which the expansion connects. Therefore, users of expansion can use existing WCs located in the existing building as well as users of the existing building can use the new WCs in the expansion area.

For purposes of the above mentioned credit (Indoor Water Use Reduction) can we perform water use calculations only considering expansion foreseen occupancy and new WCs (i.e., without considering the existing building) ?

Thanks in advance.