To calculate FTE (Full-Time Equivalent) for indoor water use, you typically need the following factors:
The amount of water used in the baseline design case: This refers to the estimated amount of water that would be used by the building's occupants under normal operating conditions. This can be based on factors such as the number of occupants, their behavior, and the types of fixtures installed in the building.
The flush and flow rates of fixtures: This refers to the rate at which water is used by various fixtures in the building, such as toilets, faucets, and showers. The flow rates can be measured in gallons per minute (GPM) or liters per minute (LPM), and the flush rates can be measured in gallons per flush (GPF) or liters per flush (LPF).
The type of building occupant (full time, part time, transient): This refers to the nature of the building's occupants and their expected water usage patterns. For example, full-time occupants may use more water than part-time or transient occupants.
Hours worked per week: This refers to the number of hours that the building's occupants are expected to be on site and using water. This factor can be used to estimate the amount of water used during different times of day and days of the week.
Building density is not typically a factor in calculating FTE for indoor water use, as it is more relevant for outdoor water use.