We are working with a school that is struggling to meet the prerequisite given programming and district requirements. The project currently plans to install 1.28 gpf toilets, 0.5 lavs, 1.3 gpm showers, and a 0.5 kitchen sink. 0.125 gpm urinals are only provided in the public restroom that will only be used by transient visitors. All staff restrooms are co-ed, therefore urinals are not provided. Urinals are also deemed not appropriate for elementary student use so not installed in student restrooms.

Our main barrier is that the students represent the main occupant water use category. Because the 1.28 gpf toilet represents exactly a 20% water use reduction but the 0.5 lavatories are baseline, the relatively minor water use of other fixtures and occupancy categories don't make up for the negative impact of the lavatories.

My question has to do with the lavatories used by students. The project could meet the prerequisite requirements with metered faucets provided for student hand washing. Unfortunately, metered faucets are not possible because the lavatories used for student hand washing are also used for other classroom functions where metering would be disruptive.

Has anyone run into a similar situation where the fixtures appropriate for the school programming do not meet the 20% minimum? Is there any argument for categorizing the student lavatories differently because they are used for other purposes?