Rough-in inspection shall be made when which of the following?

• A. After fixtures are installed
• B. During rough-in and after fixtures are installed
• C. During rough-in and before fixtures are set
• D. After the system is in operation

Answer: (C)

Rough-in inspection is done while the piping is still exposed, before anything is hidden behind walls or floors. The goal is to verify that the layout, connections, slopes, venting, trap placements, cleanouts, and supports meet code before fixtures are set. If you wait until after fixtures are installed, you can’t access concealed piping to check these details, and changes become costly or impractical. A post-installation or operational test checks function, not the proper installation stage. So the timing must be during rough-in and before fixtures are set.