Fixing a Leaky Sink

A dripping faucet or water pooling from a leak under your kitchen sink might seem like a minor annoyance, but addressing the issue quickly can save you from serious headaches down the road.

The average family can waste 180 gallons per week from household leaks — that’s 9,400 gallons annually. Beyond the environmental impact, that wasted water is driving up your water bills and potentially causing water damage to your property.

By understanding where your leak is coming from, following proper safety procedures and knowing when to call a professional, you can stop the drip and protect your home.

Determining When You Need a Professional

Not every leak is a DIY project. In fact, some situations require professional expertise to prevent further damage or ensure the repair meets plumbing codes.

You’ll want to call a plumber right away if you’re dealing with:

Sewage backups.
Complete water loss.
Burst pipes.
Leaks near electrical wiring.

These scenarios pose immediate health and safety risks that demand expert attention. Beyond emergency situations, DIY repairs aren’t appropriate for complex issues like:

Corroded pipes needing replacement.
Mainline problems affecting multiple fixtures.
An inability to identify the leak’s source.

Additionally, if you’ve attempted a repair and the leak persists, it’s time to bring in a professional who can diagnose the underlying issue.

A professional diagnosis prevents further damage by addressing the root cause rather than just treating symptoms. It also ensures all work meets local codes and provides the specialized expertise needed for tricky repairs that could otherwise lead to bigger issues.

Identifying Where the Leak Is Coming From

Before you can fix a sink leaking issue, you need to pinpoint the source. Start by distinguishing between a minor drip and an active leak, as this will help you understand the urgency of the situation. A slow, occasional drip might be a worn washer, while a steady stream or pooling water signals a more urgent problem.

Next, check if the leak is from your faucet by running water and watching for dripping from the spout or around the handles. A dripping faucet fix often starts with identifying whether water escapes from the spout or the base, which tells you which components to inspect.

For a leaking kitchen sink, you’ll need to open the cabinet and use a flashlight to inspect the P-trap, pipe connections and drain assembly. As you examine these areas, look for moisture, water stains or active dripping to help you find the problem area.

To identify leaks at pipe joints or compression fittings, carefully examine all connection points where pipes meet. Watch for moisture, mineral deposits or corrosion around compression fittings, as these signs often indicate where the seal has failed.

Important Rules to Follow for Safety

Safety should always come first when working on any plumbing repair. Following these essential precautions will protect you and your home from accidents or additional damage:

Switch off the water: The shut-off should be directly under your sink. Turn it in a clockwise direction until it’s tight. If these valves don’t work or aren’t present, shut off your home’s main water valve instead.
Place a bucket and towels under your work area: This catches trapped water and spills, protecting your cabinets.
Wear safety glasses and gloves: Safety glasses protect your eyes from debris and splashing water, while gloves give you a better grip and protect your hands from sharp edges and grime.
Plug the drain with a stopper or rag: This prevents small components like screws and washers from falling down the drain and creating another problem.
Keep your workspace clear and well-lit: Remove unnecessary items from under the sink and use a flashlight to see clearly.

General Tools and Materials You’ll Need

Having the right tools on hand makes any repair easier and more efficient. For most sink leak repairs, you’ll need:

An adjustable wrench.
Teflon tape, also known as plumber’s tape.
A bucket.
Towels.
A flashlight.
Flathead and Phillips screwdrivers.
Replacement washers, O-rings or gaskets.
Plumber’s putty for sealing drain connections.

Types of Leaks and How to Fix Them

Understanding which type of leak you’re dealing with will help you choose the right fix.

Faucet Leaks

A dripping faucet is one of the most common plumbing issues. To address this type of leak, follow these steps:

Turn off the water supply valves under the sink.
Remove the faucet handle using an Allen wrench or screwdriver.
Inspect and replace worn washers, O-rings or the entire cartridge with exact replacement parts.
Reassemble the faucet carefully.
Turn the water back on slowly and test for leaks.

Drain or Strainer Leaks

If water is leaking from your sink drain, the seal has likely failed and needs attention. Fix drain or strainer leaks by doing the following:

Place a bucket under the drain.
Check if the leak is from the strainer basket or lower drain connections.
Try tightening connections first with your adjustable wrench.
If the leak persists, remove the strainer or drain assembly.
Replace old washers and gaskets. Apply fresh plumber’s putty and reassemble.
Run water and check all connection points for leaks.

P-Trap Leaks

A P-trap is the curved pipe beneath your sink. When a P-trap leaks, it’s often due to worn washers or loose connections.

Use these steps to fix a P-trap leak:

Put a bucket under it.
Loosen the slip nuts at both ends using your adjustable wrench.
Remove the P-trap and empty the water into your bucket.
Inspect washers and gaskets for cracks or wear.
Clean the P-trap and replace worn washers. Apply plumber’s tape if needed.
Reassemble by hand-tightening first, then snug with your wrench — don’t overtighten.
Turn the water on and check for drips.

Pipe Connection or Compression Fitting Leaks

Leaks at pipe joints often occur at supply lines or where pipes connect under the sink, and they’re typically caused by loose fittings or worn compression rings.

Follow these six steps:

Identify the exact leak point.
Try hand-tightening the compression nut first.
If the leak continues, turn off the water and use your wrench to tighten it slightly.
If still leaking, disassemble the connection completely.
Inspect the compression ring for damage and replace it if needed. Apply fresh plumber’s tape to threads.
Reassemble carefully and test for leaks.

Preventive Maintenance Tips

Preventing leaks is easier than learning how to fix a leaky sink, and a little routine maintenance goes a long way toward avoiding repairs and keeping the drain clear. Make it a habit to regularly inspect under your sink for moisture or early signs of a leak. Once a month, check all connections, the P-trap and supply lines with a flashlight.

Avoid harsh chemical drain cleaners that can corrode pipes over time, and do not pour clogging agents like grease down the drain.

Schedule professional plumbing inspections periodically to spot potential issues you might miss.

Get Expert Help From Strada Services

If you’re dealing with a persistent sink leak from the cabinet pipes, corroded pipes or something you can’t identify, Strada Services is here to help. As a fully licensed plumbing company, we provide comprehensive sink leak diagnosis and repair services for homeowners. Our highly trained and professional technicians can handle all types of sink and pipe leaks.

Family-owned and operated since 2003, we’ve built our reputation on core values of accountability, honesty and commitment. We offer 24/7 phone support, so you can reach our team anytime to schedule an emergency or routine plumbing appointment.

Schedule your appointment online or call our 24/7 line at 833-539-7800.