Sink and Lavatory Installation

Why This Matters on the Exam

Sink and lavatory installations are everywhere - you're gonna do dozens of these in your career. Residential and commercial applications have different requirements, but they all follow the same core principles. The California Plumbing Code is specific about mounting methods, clearances, drainage setup, and accessibility. I've seen expensive callbacks because someone got the P-trap wrong, missed an ADA requirement, or reversed the hot and cold. The exam tests your knowledge of mounting types, drainage requirements, faucet installation, and accessibility standards. Get these details right and you've got solid, reliable installs.

What You Must Know

Here's the deal: hot water supply always connects on the of the fixture when facing it; cold on the . All sinks require a - that curved trap that holds standing water to block sewer gases from coming back up. The trap should be installed as close as practical to the fixture outlet. ADA lavatories sit at the rim, with underneath (19 inches deep). You've got different mounting types - drop-in, undermount, farmhouse/apron front for kitchens; wall-hung, pedestal, and vanity lavatories. All drains need (1 inch minimum) between the faucet outlet and the sink rim to prevent backflow. Garbage disposals need separate drain lines with their own P-traps. Always install escutcheons around supply line holes.