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How To Repair A Leak Under the Kitchen Sink

Resolving under-sink leaks is crucial since they can cause a lot of damage to your kitchen if neglected. Thankfully, leaks under the sink are easy enough to spot, making it simpler to repair than many other internal plumbing issues. A kitchen sink faucet leaking underneath your cabinets or a dripping drain pipe is certainly annoying, but being able to spot the leak early helps prevent serious damage.

Repairing a leak under the kitchen sink can be as simple as tightening a connector piece, but it can also be far more complicated, requiring large replacements or professional repairs. It all depends on where the leak is coming from.

How Do You Fix A Leak Under The Kitchen Sink?

Properly fixing an under-sink leak begins with an assessment of the situation. Different types of leaks require different repairs, so the kitchen faucet leaking under the sink is a different job then the drain pipe leaking. You must determine where your leak is to fix it.

Sink leaks are usually discovered by first noticing signs of water damage, such as water on the floor near the sink or dampness in the cabinet under the sink. This could be as small a sign as a bit of moisture or a full-on pool of standing water.

If you notice signs of water damage, clear everything out from under your sink and grab a flashlight to look around. Check the piping and drain line for any loose fittings. Check the sealant around the sink drain and faucet for any faulty caulk. You may need to turn on the water to see where it drips, or even fill the sink and let the water stand for a few minutes before the leak appears. Have a towel or a bucket ready to collect any leakage. Once you determine the location of the leak, you can figure out how to repair it.

Why Is My Kitchen Sink Leaking Underneath?

There are many different reasons why your sink might be leaking underneath, but some issues are more common than others. Once you’ve identified where your leak is, it’s much easier to determine why it’s happening. There are a few common reasons why you have a leak under the kitchen sink.

Drain Leak

Drains are typically sealed with some kind of putty or sealant to keep it from leaking, but this putty could have been put on too thin or it could dry out and crack over time. If this is the case, you may just need to replace the sealant to repair the leak. You also might be able to get away with tightening the nuts where the pipes meet to stop the leak, especially if there’s a leaking pipe under the kitchen sink.

If you have a more serious issue, however, then both of these options would be temporary fixes, which are effective in the short-term and not in the long run. Some old drains become too worn and are beyond hope for repair, requiring a full replacement. In instances like this, it’s best to contact a professional plumber to handle your drain repair.

Clogged P-Trap

The P-Trap is the curved section of pipe found under the sink, and it can be the leaking pipe under the kitchen sink that you’ve been searching for.  It’s designed to keep foul smells from coming up through the drain but over the course of time, debris like food pieces and other elements dropped down the drain can clog up. This prevents proper drainage and can cause a leak in some instances. Your P-Trap could also be leaking due to corrosion, incorrect installation, fit issues, and more, so fixing a leaky P-Trap depends on the exact problem at hand. Consider consulting your plumber before attempting to fix it.

Corroded Valve Seat or Worn Out Washers

Water and time have a tendency to wear down many different materials, including metal valves and rubber washers. If this happens to the valves and washers holding your sink and piping together, a leak can occur.

A decaying washer is one of the most common causes of sink leaks, since every time the faucet is used, the washer is pressed against the valve seat. Friction from continual use can cause the washers to wear out. The valve seat connects the spout and the faucet for the compression mechanism, but water accumulation can cause it to corrode.

While washers are easy to replace, the valve can be more complicated. Getting the valve seat cleaned by a professional plumber regularly is a great way to prevent corrosion and a leak.

Faucet Leak

The kitchen faucet leaking under the sink is a fairly common issue. A leak coming from the faucet is easy to spot since water often pools up around it when the sink is turned on. Alternatively, it could leak water under the sink, meaning you’ll only notice the leak if you look under the counter while the faucet is on. This type of leak is usually caused by a worn-down gasket or faulty washer. A severe leak will require a full faucet replacement but in most cases, a small repair will resolve the leak.

A Leak Under The Kitchen Sink Calls For A Plumbing Expert

Under the sink leaks, such as a kitchen sink faucet leaking underneath your cabinets or a corroded pipe causing continual drips, can cause a lot of damage unless they’re addressed right away. While there are many leaks you can attempt to repair yourself or temporary fixes you can implement to prevent a huge amount of damage, it’s always a good idea to have a professional plumber examine your leak to make the best repair possible. Contact John C. Flood’s expert team to resolve any kind of under sink issue.