We have a small TI project that is struggling with the WEp1 credit.

We have built out a suite in a building that already qualified for LEED Certified. We are now struggling to get a 20% further reduction from what the base building has accomplished without affecting the quality for the other residents on our floor. (Kits to reduce urinal and water closet numbers are causing serious water pressure issues.) Can we make the case that the base building already met the 20% reduction and then work on reducing flow within our suite?