Is Your Bathroom Sink Leaking? Here’s How to Fix it! 

By: Diana Rodriguez-Zaba
Updated on: March 29, 2024

Have you noticed pooling water on the floor or inside your cabinets? If so, you must act fast – your bathroom sink is probably leaking. 

Fortunately, we’re here to help.

With over 85 years of combined experience, we’ve helped hundreds of homeowners deal with leaky bathroom sinks and clean up water damage.

In this blog, we’ll share our top tips for repairing a leaking bathroom sink and getting life back to normal as quickly as possible. 

Before You Get Started

sink leaking underneath

Shut Off the Water

To mitigate the risk of water damage and prevent the situation from worsening, it’s essential to promptly locate and turn off the water supply valve of a leaky bathroom sink. 

This step is the foremost safety measure and helps in avoiding additional complications.

Gather Necessary Tools and Equipment

Before addressing a leak under the kitchen sink, ensure you have the right tools and materials ready. 

Essential items include the following:

  • A bucket to catch dripping water
  • Adjustable wrenches or pipe wrenches for loosening and tightening fittings
  • A flashlight for better visibility
  • Plumber’s tape to seal thread connections
  • Replacement parts like washers or gaskets that may need to be replaced 

Having these items on hand will streamline the repair process and reduce the time your kitchen is out of commission.

Assess the Severity and Complexity of the Leak

Evaluate the leak’s source and the extent of potential damage to determine whether it’s a simple fix or a complex issue requiring specialized skills. 

Leaks that only involve replacing a worn washer or tightening a loose fitting might be suitable for DIY repairs. 

However, if the leak involves major plumbing lines, shows signs of significant damage to the sink or cabinetry, or if you’re unable to identify the source, it’s prudent to consult a professional plumber. 

This ensures the problem is resolved effectively and prevents further damage or costly complications.

How To Fix A Leaking Bathroom Sink

how to fix a leaking bathroom sink

How you fix a sink leak depends on the cause. Here’s what you need to know about various kinds of leaks and how to address them:

Leaks in the Hoses

  • Signs: Check for water leaking from the hose or around connections.
  • Cause: Loose or damaged connections.
  • Fix: Tighten connections with pliers; replace the internal gasket if needed.
  • Pro Tip: Ensure connections are securely tightened to prevent future leaks.

P-Trap Leak

  • Signs: Water is pooling under the sink, and there is dampness around the p-trap area.
  • Cause: A loose slip nut or damaged p-trap.
  • Fix: Tighten the slip nut with hand tools; use a pipe wrench if needed.
  • Pro Tip: Check for corrosion on the p-trap during maintenance.

Shut-Off Valve Leak

  • Signs: Dripping water from the shut-off valve.
  • Cause: Wear and tear on the valve.
  • Fix: Evaluate valve condition; hire a plumber if soldered on.
  • Pro Tip: Regularly check shut-off valves for any signs of leakage.

Drain Leaks

  • Signs: Water leaking from the sink’s drain assembly.
  • Cause: Damaged drain components.
  • Fix: DIY by replacing p-trap and drain; wrap drain threads in plumber’s tape.
  • Pro Tip: Seek professional help for complex drain assembly leaks.

Connection Leak

  • Signs: Moisture or water around sink connections.
  • Cause: Loose connections or worn-out hardware.
  • Fix: Tighten connections with pliers; replace hardware if necessary.
  • Pro Tip: Periodically check and tighten sink connections to prevent leaks.

Handle Leak

  • Signs: Water leaking from the faucet handle.
  • Cause: Damaged handle or internal components.
  • Fix: Replace the handle following manufacturer instructions.
  • Pro Tip: Check for any signs of leakage to maintain faucet functionality.

How To Deal With The Water Damage

sink water damage cleanup

If a bathroom sink is leaking underneath, every drip causes water damage. Once you’ve stopped the leak, you’ll also need to repair the water damage. 

Here’s why:

Over time, water damage builds up, increasing your bathroom’s humidity and causing potential mold growth

Once mold forms, it can cause various adverse health consequences for vulnerable populations, including children, people with allergies, and older adults. Mold also makes your bathroom smell damp and musty. 

If you’ve discovered a water leak in your bathroom, contact a water damage restoration company to evaluate the damage and repair any rotted wood, mold, or other damage that may be present. 

How To Prevent Leaking Bathroom Sinks

  • The best way to prevent leaking bathroom sinks is to inspect and repair your sink routinely. Replacing aging components before they wear out entirely allows you to stop leaks in their tracks and prevent the water damage they cause. 
  • Check your home’s water pressure regularly. The ideal home water pressure is between 40 and 60 psi. Water pressure higher than that can cause broken or burst pipes, leading to a leak. 
  • To check for leaks, consider placing a few pieces of paper towel in your bathroom vanity beneath your sink’s pipe fittings. Check the paper towels regularly for signs of water stains or dampness, which could indicate the presence of a new leak. 

Are You Dealing With A Leaking Bathroom Sink In Chicago? We Can Help!

You don’t have to live with a leaky sink forever! Contact the team at ServiceMaster Restoration by Zaba for professional plumbing leak cleanup you can trust.

As a team of leading restoration experts, we understand how to diagnose and pinpoint sink leaks and repair the water damage they create.

Contact us today to request service or to learn more about our team and how we can help you: (773) 647-1985

Is a bathroom sink leak dangerous?

Yes, a bathroom sink leak can be potentially dangerous. While a leak might seem minor at first, it can lead to significant water damage over time, affecting cabinetry, flooring, and – if left unattended – the structural integrity of your home. Additionally, persistent moisture from leaks creates an ideal environment for mold and mildew growth, which can pose health risks. To prevent these hazards, address any leaks as soon as they are detected.

How much does it cost to repair a leaking bathroom sink?

The cost to repair your leaking bathroom sink will depend on a few factors, including the cause of the leak, the extent of the water damage, and what kind of replacement parts your sink requires. 

Are leaks covered by homeowners’ insurance?

Most homeowners insurance policies cover water damage that is “sudden and accidental,” like burst pipes. Your policy might not cover gradual damage from a leaking bathroom sink or a faulty appliance, though, so it’s essential to stop these problems in their tracks.

What causes a dripping bathroom sink?

A dripping bathroom sink is annoying, but it can also be a big deal for your home. Usually, dripping sink faucets are caused by defective O-rings, washers, gaskets, or other parts. If these parts aren’t replaced quickly, the slow drip can lead to water damage that impacts your home’s drywall, flooring, or vanity under your sink.