What is the MOST appropriate way to determine the number of lavatories required in a...

The number of lavatories required in a commercial restroom is determined by plumbing codes, which are based on the building’s occupancy type and occupant load. The International Plumbing Code (IPC) or local plumbing codes specify the minimum number of fixtures (e.g., lavatories, toilets) required per occupant load, ensuring adequate facilities for hygiene and safety. Consulting the plumbing code based on the building’s jurisdiction is the most appropriate method, as it provides a legally binding standard. Option A (interview the client) may provide user data but does not ensure code compliance. Option B (create a floor plan) determines space availability, not the required number of fixtures.

Verified Answer from Official Source:

The correct answer is verified using NCIDQ IDFX content on plumbing codes.

Exact Extract:TheNCIDQ IDFX Reference Manualstates, “The number of lavatories in a commercial restroom must be determined by consulting the plumbing code based on the building’s jurisdiction, which specifies fixture requirements by occupancy and load.”

The NCIDQ IDFX curriculum requires designers to apply plumbing codes to ensure compliance with health and safety standards in commercial restrooms.

Objectives:

Apply plumbing codes to restroom design (IDFX Objective: Codes and Standards).