How To Replace A Kitchen Sink And Faucet: Step-by-Step

Yes, you can replace a kitchen sink and faucet yourself; it is a manageable DIY project for most homeowners, provided you have basic plumbing skills and the right tools. Replacing a kitchen sink and faucet revitalizes your kitchen. It can also fix leaks or update outdated fixtures. This guide walks you through the entire process, from preparing for the job to the final tightening of the nuts. We will cover both drop-in and undermount sink removals and installations.

Getting Ready for Your Kitchen Sink Swap

Proper preparation saves time and frustration. Before you start ripping things out, gather your tools and materials. Make sure your new sink and faucet are ready to go.

Tools You Will Need

You need a specific set of tools for this job. Having everything on hand makes the work much smoother.

Tool	Purpose
Safety Glasses & Gloves	Protect your eyes and hands.
Adjustable Wrench or Basin Wrench	Essential for reaching tight nuts under the sink.
Screwdriver Set	For cabinet hardware or faucet mounts.
Utility Knife or Putty Knife	To cut old caulk and sealant.
Bucket and Towels/Rags	To catch water during disconnection.
Channel Locks (Pliers)	For gripping and turning larger plumbing fittings.
Flashlight or Work Light	To see clearly under the cabinet.
Caulk Gun and Silicone Caulk	To seal the new sink to the countertop.
Plumber’s Putty	For sealing drains and strainers.
Hacksaw or Oscillating Tool (Optional)	For cutting old drain pipes if necessary.

Materials Checklist

Ensure you have all the parts for installing a new kitchen sink.

New Kitchen Sink
New Faucet Assembly
New Drain Baskets/Strainers (usually come with the sink)
Supply Lines (if your new faucet needs different ones)
Mounting hardware for kitchen sink (clips, screws)
New Garbage Disposal (if replacing)

Phase 1: Removing the Old Sink and Faucet

The old sink removal process requires careful disconnection of all connected lines. Always turn off the water first.

Shutting Off Water Supply

Locate the shut-off valves under the sink cabinet. Usually, there is one for hot water and one for cold water.

Turn both valves clockwise until they stop. This shuts off the water flow to the faucet.
Turn on the old faucet to release any built-up pressure. Let the water drain completely.

Disconnecting Plumbing Connections

This is the tricky part of plumbing for kitchen sink replacement. Have your bucket ready.

Place the bucket directly beneath the P-trap and tailpieces.
Use channel locks or an adjustable wrench to loosen the slip nuts connecting the tailpieces to the P-trap. Water will drip out.
Disconnect the drain lines completely.
If you have a dishwasher drain line connected, detach it from the disposal or the sink tailpiece.

Disconnecting the Garbage Disposal

If you have a garbage disposal, disconnect it next.

If the disposal is hardwired, turn off the power to that circuit at the main breaker panel. Safety first!
Unplug the disposal if it has a standard plug.
Use a screwdriver to loosen the mounting ring screws holding the disposal to the sink flange.
Twist the disposal unit counter-clockwise to detach it from the mounting assembly. Set it aside.

Removing the Old Faucet

Replacing kitchen faucet and drain often happens at the same time.

Use a basin wrench to reach up behind the sink basin. Locate the mounting nuts holding the faucet onto the sink deck or countertop.
Loosen these nuts completely.
From above the sink, lift the old faucet assembly out.

Detaching and Removing the Sink

The removal method depends on whether you have a drop-in or undermount style sink.

Drop-in Sink Removal Process

Drop-in sink removal is usually simpler. These sinks rest on top of the counter edge.

Use a utility knife to score and cut through the bead of old caulk or sealant around the entire rim of the sink. Cut deeply to ensure you break the seal.
Get underneath the sink. Check for clips or screws holding the sink down from below. Remove all mounting hardware for kitchen sink.
Carefully try to lift the sink from beneath. If it’s stuck, gently tap the underside with a rubber mallet to break the remaining seal.
Once free, lift the entire unit straight up and out of the counter opening.

Undermount Sink Installation Guide (Removal)

Undermount sink installation guide often involves more demolition during removal. These sinks are glued and clipped directly beneath the countertop.

Ensure all water and drain connections are fully disconnected.
Locate the metal clips screwed into the underside of the countertop, holding the sink rim tight. Remove all mounting screws.
Use a block of wood and a hammer to gently tap upward on the sink bottom to break the adhesive bond. Do not hit the countertop!
Once free, slowly lower the sink and remove it. Countertops can be heavy, so this usually requires two people.

Cleaning the Opening

Thorough cleaning is vital for a good seal with the new unit.

Use a putty knife to scrape away all old caulk, putty, and adhesive residue from the countertop opening.
Wipe the area clean with mineral spirits or rubbing alcohol. The surface must be dry and smooth.

Phase 2: Preparing the New Sink and Faucet

It is much easier to install the faucet and drains onto the new sink before setting the sink into the counter.

Faucet Installation on the Sink

Whether you have a stainless steel, composite, or porcelain sink, follow these steps to set the faucet hardware.

Read your new faucet manual carefully.
Place the base gasket or escutcheon plate over the faucet holes on the sink deck.
Feed the faucet lines (hot/cold/spray hose) through the correct holes from the top.
From underneath the sink, slide on any washers or mounting plates that came with the faucet.
Hand-tighten the mounting nuts first.
Use your basin wrench to securely tighten the nuts, ensuring the faucet is straight and facing forward. Do not overtighten, which can damage the sink deck.

Installing Strainers and Drains

This step seals the drain openings. Use plumber’s putty for this, not silicone caulk, unless specified by the manufacturer.

Roll a thin rope of plumber’s putty and press it around the underside lip of the sink drain flange (strainer basket).
Press the strainer firmly into the drain opening from above the sink.
From below, thread the gasket, friction washer, and locknut onto the strainer body.
Tighten the locknut securely with channel locks. Wipe away any excess plumber’s putty that squeezes out around the top edge.

Connecting Garbage Disposal to New Sink

If you are connecting garbage disposal to new sink, you must install the disposal mounting ring onto the new sink flange first.

Apply plumber’s putty under the lip of the new sink flange (the visible metal rim that sits in the drain hole).
Press the flange into the drain hole.
From below, attach the mounting assembly bracket, fiber gasket, and lock ring onto the flange. Tighten the lock ring firmly.
Lift the disposal unit up to the mounting ring and twist it securely into place until it locks.

Phase 3: Setting the Sink in Place

This phase differs significantly based on your sink type.

Setting a Drop-In Sink

DIY kitchen sink replacement is often easiest with a drop-in model.

Apply a continuous bead of 100% silicone caulk around the underside edge of the countertop opening where the sink rim will sit. This creates the waterproof seal.
Carefully lower the sink, with the faucet and drains already attached, into the opening. Align it so it sits evenly.
Check the fit from above. Adjust it slightly if needed before the caulk sets.
Install the mounting hardware for kitchen sink (the clips) underneath the counter rim. Tighten these clips gradually, alternating sides, to pull the sink flange down snugly against the countertop. This squeezes out excess caulk.
Wipe away all excess silicone caulk immediately using a damp cloth or your finger dipped in mineral spirits.

Executing Undermount Sink Installation

Undermount sink installation guide requires adhesive and strong support until cured.

Apply a thick, continuous bead of strong adhesive (epoxy or specialized sink adhesive) to the underside rim of the sink. Some installers also apply a thin bead to the underside of the countertop lip.
Lift the sink into position under the counter. This often requires a helper or a temporary support jack positioned beneath the sink basin.
Align the sink perfectly. The clips you removed earlier are reattached now. Secure the mounting hardware for kitchen sink clips tightly to pull the sink tight against the adhesive.
Allow the adhesive to cure fully according to the manufacturer’s directions before reconnecting any plumbing (usually 12 to 24 hours). If you skip the cure time, the sink might detach when you apply weight or water pressure.

Phase 4: Reconnecting the Plumbing

Now we focus on kitchen sink plumbing connections below the counter.

Reconnecting Supply Lines

Attach the new flexible supply lines from the faucet shank ends to the shut-off valves.
Ensure connections are tight—hand-tight plus about a quarter turn with a wrench. Do not force them.

Reconnecting the Drain System

This requires reconnecting the tailpieces to the P-trap and ensuring all gaskets are seated correctly.

Reinstall the tailpiece pipe coming down from the sink drain (or garbage disposal flange).
Connect the P-trap assembly to the wall drain pipe.
Hand-tighten all the slip nuts.
Check the alignment. The drain lines must flow downward consistently without kinking or straining the joints.
Once aligned, use channel locks to give each slip nut about a half-turn more to secure the seal. Do not overtighten plastic fittings, as they can crack easily.

Finalizing Garbage Disposal Connection

If you installed a disposal, reconnect its drain line to the P-trap assembly. Ensure the hose clamp is tight where the disposal output meets the trap pipe.

Phase 5: Testing and Final Checks

Never skip the testing phase, as this is where you catch slow leaks.

Testing the Faucet

Ensure the faucet handles are in the OFF position.
Go back under the cabinet and slowly turn the hot and cold water shut-off valves counter-clockwise. Listen for any hissing sounds.
Turn on the faucet, running both hot and cold water for several minutes.

Inspecting for Leaks

This is crucial for any plumbing for kitchen sink replacement.

Check every connection you touched: the faucet supply line nuts, the disposal mounting ring (if applicable), and all P-trap slip nuts.
If you see a slow drip, turn the water off immediately. Tighten that specific connection slightly more. Repeat testing.
If leaks persist after slight tightening, disassemble that joint, check that the rubber gasket or washer is seated correctly, and reassemble.

Final Cure Time

If you installed an undermount sink, avoid heavy use for the cure time specified by your adhesive. For drop-in sinks, the silicone caulk usually needs 12 to 24 hours to cure before you can seal the final exterior bead of caulk around the rim (if you waited to do the exterior seal).

Congratulations! You have completed your DIY kitchen sink replacement. A clean kitchen requires regular maintenance, so check these connections periodically over the next few weeks.

Frequently Asked Questions (FAQ)

How long does it take to replace a kitchen sink and faucet?

For an experienced person replacing a drop-in sink, it can take 3 to 5 hours. If you are replacing an undermount sink, dealing with old adhesive, or installing a garbage disposal for the first time, the job can easily take a full day (6 to 8 hours), especially if you have to wait for adhesives to cure.

Do I need plumber’s putty or silicone caulk for sealing?

You use both. Plumber’s putty is used to seal around the drain flanges (strainers) because it stays pliable and resists hot water well. Silicone caulk is used to create a waterproof barrier between the edge of the sink rim and the countertop surface.

Can I reuse the old plumbing connections?

It is strongly recommended that you replace all flexible supply lines and any plastic drain gaskets when replacing kitchen faucet and drain assemblies. Old rubber gaskets often become brittle, leading to leaks shortly after reassembly.

What tool is best for reaching mounting nuts under the sink?

A basin wrench is the absolute best tool for this task. It has a long handle and a swiveling jaw designed specifically to grip and turn nuts in the tight space behind the sink bowl where traditional wrenches cannot reach.

What is the difference between drop-in and undermount sinks?

A drop-in sink (or top-mount) has a visible rim that sits over the countertop material, making installation easier. An undermount sink is mounted beneath the countertop, creating a seamless look where the counter edge meets the basin opening. Undermount sink installation guide steps are more complex due to the required adhesives and support.