The short answer
Signs of a Leaking Drain
Start by looking under your sink with a flashlight. Check the drain pipes, the P-trap, and the slip nuts where pipes connect. Any water droplets, mineral buildup, or rust on metal parts point to a leak. Also feel the cabinet floor for dampness or soft wood.
Run water for a minute while you watch the pipes. Look for drips at the joints and along the bottom of the P-trap. A musty odor inside the cabinet often means moisture has been sitting there. If you see or smell any of these, your drain is likely leaking.
- Water stains on the cabinet bottom
- Damp or warped wood under the pipes
- Visible drips when water runs
- A persistent musty smell
- Slow draining water
- Loose or corroded pipe connections
Where to Check First
The P-trap is the curved pipe under your sink, and it is a common leak spot. Check where it connects to the tailpiece from the sink and to the wall pipe. Tighten slip nuts by hand, but do not overtighten, as that can crack the threads.
Also inspect the basket strainer inside the sink bottom. A leak here shows as water on top of the cabinet, not underneath. Feel around the strainer for moisture. If the leak is at the wall pipe, you may need a plumber to reseal the connection.
What Causes Drain Leaks
Drain leaks often come from worn-out washers or gaskets inside the slip nuts. Over time, these rubber parts dry out and crack. Pipe corrosion, especially on older metal pipes, can also create pinholes. A clogged drain can back up water and force it out through joints.
Temperature changes and minor shifts in the house can loosen connections. If your sink has a garbage disposal, check the mounting ring where it attaches to the sink. A faulty seal there leaks onto the cabinet floor. Identifying the cause helps you decide whether to fix it yourself or call a pro.
Quick Steps to Limit Damage
As soon as you notice a leak, place a bucket or a shallow pan under the drip to catch water. Wipe up any standing moisture to prevent wood damage and mold growth. Open the cabinet doors to let air circulate and dry out the area.
Turn off the water supply to the sink if the leak is severe. Look for the shutoff valves under the sink, usually two small handles. If you cannot find them, shut off the main water valve for your home. In Layton, keep your shutoff valve location written down for emergencies.
When to Call the Pros
If the leak persists after you tighten connections or replace a gasket, the damage may be deeper. Water can seep into the cabinet base, subfloor, or walls. The pros use moisture meters and leak detection equipment to find hidden water. They also dry the structure to prevent mold.
For a thorough assessment, a water damage inspection can reveal issues you cannot see. The pros can identify the exact source and recommend the right repair. They also handle cleanup and structural drying if water has spread. Acting quickly reduces the chance of costly repairs later.
- Moisture meters detect hidden dampness
- Leak detection finds the source
- Structural drying prevents mold
- Inspection covers cabinets, floors, and walls
- Cleanup includes removing damaged materials
Water damage does not wait
Water keeps spreading into floors and walls, so it is worth acting early. Calls are answered 24/7.
Call Now (801) 383-0232Frequently asked questions
How can I tell if the leak is from the drain or the water supply?
Run the water and watch the pipes. If drips appear only when water flows, it is a drain leak. If water drips constantly even with the faucet off, it is likely a supply line issue. Check both hot and cold lines for moisture.
Is a small drip under the sink a big problem?
Even a small drip can cause wood rot, mold, and attract pests over time. Moisture soaks into the cabinet and subfloor, weakening the structure. Fix it quickly to avoid bigger damage. If you cannot find the source, a professional inspection helps.
Can I fix a leaking drain myself?
You can tighten slip nuts or replace a worn gasket with basic tools. If the pipe itself is cracked or corroded, you may need to replace a section. For leaks behind the wall or under the floor, call a plumber or water damage pro.