How to Replace a Bathroom Sink
Whether you're upgrading a dated pedestal or swapping a drop-in basin, this guide walks you through shutting off the water, removing the old sink, fitting the faucet and drain, and achieving watertight connections you can rely on.
Turn Off the Water Supply
Locate the shut-off valves under the sink (or the main if there are none) and turn them clockwise until firmly closed. Then open the faucet to drain residual pressure.
Disconnect Supply Lines and P-Trap
Use an adjustable wrench to disconnect the flexible supply lines from the shut-off valves. Unscrew the P-trap slip joints by hand or with slip-joint pliers.
Remove the Old Sink
Drop-in sinks are held by clips and caulk from below; pedestal sinks bolt to the wall. Cutting the old caulk bead is often the hardest part.
Install the Faucet and Drain onto the New Sink
It is far easier to fit the faucet, pop-up drain body, and supply lines to the sink on a workbench before mounting it in place.
Mount the New Sink
Set the sink into position, secure the mounting clips or wall bolts, and apply a fresh bead of silicone around the rim for a watertight seal.
Reconnect the Drain and Supply Lines
Reconnect the P-trap and tighten the supply line nuts. Use PTFE tape on threaded metal connections to ensure a leak-free joint.
Restore Water and Check for Leaks
Turn the stop valves back on slowly and run the tap. Inspect every connection — supply lines, the P-trap, and the drain flange — with dry paper towel for any drips.
📋 Related Building Codes
IPC · Ch.4 — Fixtures, Faucets and Fixture Fittings
§403.1 · Toilet Facilities
View reference (2021) →
Always consult local codes before proceeding.
Materials Required
| Product | Qty |
|---|---|
📦Other Materials1 item | |
 2 in. x 4 in. x 8 ft #2 Premium #2 Grade Fir Dimensional Lumber | 1 |
2 in. x 4 in. x 8 ft #2 Premium #2 Grade Fir Dimensional Lumber
1
* Prices are estimates and may vary. Always verify at checkout.
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Safety & Legal Disclaimer
This guide is for informational purposes only and does not constitute professional engineering, architectural, or contractor advice. Building codes vary by jurisdiction — always verify local requirements, obtain all required permits, and consult a licensed contractor or structural engineer before beginning any construction project. Aribuilds makes no warranty as to the accuracy, completeness, or suitability of this information for any particular project. Use of this guide is at your own risk. Aribuilds accepts no liability for personal injury, property damage, structural failure, or code violations.
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