Why is Your Tap Dripping After Shut-off and How to Fix it Yourself?

Why Should You Fix a Dripping Tap Immediately?

A dripping tap isn't just an annoying sound – it also represents a real financial cost and the risk of greater damage in the long run.

Even one drip per second means hundreds of litres of wasted water over a year, directly impacting your water bill. If the water is hot, you're paying double – for both the water and its heating.

• Constant moisture around the sink encourages the formation of mould and rust stains on the basin and bathroom surfaces.
• A worn washer or cartridge can leak more severely over time, causing water damage inside cabinets or walls.
• Continuous dripping accelerates the further wear of parts within the cartridge, as moving components never get to fully rest.

Cartridge Taps vs. Two-Handle Taps – Different Causes

Before starting any repairs, it's important to identify the type of tap you have, as the internal structure and thus the repair method differ significantly.

Ceramic Cartridge – The Most Common Cause of Dripping

A ceramic cartridge consists of two tightly ground discs that move against each other when the lever is operated, opening or closing the water path. If the discs are perfectly smooth and clean, the cartridge completely seals the water and allows not a single drip through.

Over time, however, the discs can wear, scratch, or become prevented from closing completely by limescale and dirt – in which case, a microscopic gap always remains, allowing water to drip through even when the lever is fully closed.

The lifespan of a cartridge largely depends on water quality – in areas with hard (lime-rich) water, the cartridge wears out many times faster than in areas with soft water, as limescale crystals act like tiny sandpaper, scratching the ceramics with every use.

• The average lifespan of a ceramic cartridge is 5–10 years, but in hard water areas, it may be only 2–4 years.
• The cartridge is typically a replaceable part that doesn't require ordering a separate tap body – most manufacturers sell only the cartridge as a spare.
• When replacing a cartridge, it is crucial to choose the exact matching size and model, as cartridges are not universal.

Rubber Washers and O-Rings

In addition to the cartridge or valve spindle, a tap uses several smaller rubber washers and O-rings that seal connections and keep water flowing in the desired direction.

If these seals age, harden, or crack, they no longer press tightly enough against the metal or ceramic surface, which can cause dripping not only directly from the spout but also from under the tap body or around the handle.

Limescale and Dirt – A Quiet, But Significant Cause

Estonian tap water in many regions, especially Harjumaa and other areas with limestone groundwater layers, is quite hard, meaning it contains abundant calcium and magnesium salts. These salts gradually deposit wherever water flows and slowly evaporates or stands – including between the cartridge discs and on the surface of washers.

The limescale layer may not be immediately visible to the naked eye, but even a thin film prevents the cartridge discs from closing completely, leaving a small gap through which water drips.

The good news is that dripping caused by limescale can often be resolved without replacing a part – simply remove the cartridge or washer and thoroughly clean it in a vinegar or descaler solution.

• Soak the cartridge or washer in a diluted vinegar solution for 20–30 minutes to soften the limescale.
• Use a soft brush (such as an old toothbrush) to remove visible deposits from between the discs and edges.
• Rinse the part thoroughly with clean water before reassembling it into the tap.
• If limescale has already caused deep scratches to the ceramic, cleaning will no longer help, and the cartridge must be replaced.

Excessively High Water Pressure as a Cause of Dripping

While most dripping incidents stem from worn parts, excessively high water pressure in the house or flat can also be the cause. If the pressure in the piping is higher than normal, the cartridge or washer must withstand greater force to stop water flow, and even very minor wear that wouldn't cause dripping at normal pressure will start leaking at higher pressure.

High water pressure can be related to the general plumbing setup of the house, a central booster pump in an apartment block, or a fault in the main boiler. If you notice several taps in the house dripping simultaneously or water flowing from the tap with an unusually strong stream, it's worth checking the overall water pressure – we have written more about this in our article on apartment water pressure.

Incorrect Installation or Improperly Assembled Cartridge

Sometimes the cause of dripping isn't wear, but simply that the cartridge or washer isn't installed correctly. If the spare part was inserted the wrong way during a previous repair, slightly askew, or not fully seated in its recess, it may not close correctly even when brand new.

Similarly, problems can arise if the cartridge retaining nut isn't tightened sufficiently – in this case, the cartridge won't press its internal discs together with enough force, leaving a small gap for water to pass through.

• Check if the cartridge or valve body has a specific direction or marker that must remain in a certain position.
• Ensure the retaining nut is tightened firmly, but not overtightened, which can damage the cartridge.
• If the repair was done recently and dripping occurred immediately afterwards, incorrect installation is a more likely cause than new wear.

How to Precisely Determine Where the Water is Coming From?

Before repairing, it's worth spending some time on careful observation – this helps choose the correct repair strategy and saves time and potential unnecessary spare part purchases.

• Using a dry, clean cloth, wipe the entire tap and its surroundings dry, then observe for a few minutes to see where the first drip appears.
• Check if dripping only occurs when one specific side (hot or cold) has been open, or in both cases.
• See if water comes directly from the spout, under the lever, from the body joints, or from between the tap base and the basin.
• If dripping only occurs after using hot water, this may indicate thermal expansion in the cartridge, which is an additional sign of wear.

Required Tools and Materials for Repair

Most tap repairs can be done with simple household tools, without immediately needing to call a professional.

• Screwdriver (flat and Phillips head) for removing the handle cover and fixing screw.
• Adjustable spanner or wrench for loosening the cartridge retaining nut.
• New ceramic cartridge or washer kit that perfectly matches your tap model.
• Cleaning cloth, old toothbrush, and vinegar or descaler for limescale removal.
• Silicone grease for lubricating tap moving parts after reassembly – this extends the life of the new cartridge.

Step-by-Step Guide: How to Replace a Tap Cartridge Yourself

The following guide describes the most common repair – replacing the cartridge in a single-lever mixer tap. For a two-handle tap, the steps are similar, but you'll replace the valve spindle and washer instead of the cartridge.

• 1. Be sure to close both the hot and cold water isolation valves, typically located inside the under-sink cabinet or against the wall.
• 2. Open the tap lever fully and let the remaining water pressure escape from the pipes before starting disassembly.
• 3. Remove the lever cover (often just a pushed-on plastic cap) and the retaining screw underneath it.
• 4. Carefully lift off the lever, exposing the cartridge retaining nut.
• 5. Loosen the retaining nut with a spanner and carefully lift out the old cartridge.
• 6. Clean any dirt and limescale from the cartridge housing in the tap body before inserting the new cartridge.
• 7. Place the new cartridge in the exact same position and orientation as the old one – most cartridges have a small notch or pin for this.
• 8. Screw the retaining nut back on, tighten it firmly, but don't overtighten.
• 9. Reattach the lever, fix the screw, and replace the cover.
• 10. Slowly open the isolation valves and check that the tap now closes completely without dripping.

Replacing a Washer in a Two-Handle Tap – How it Differs

For a classic tap with two separate handles, the repair logic is similar, but the parts you replace are different.

• Close the isolation valves and open the tap to release pipe pressure.
• Remove the tap handle and the cover or screw underneath it.
• Unscrew the tap spindle (valve stem with washer) using a spanner.
• Check the rubber washer at the end of the spindle – if it's flat, cracked, or hardened, replace it with a new one.
• If the spindle itself is worn or rusty, it's cheaper and more sensible to replace the entire spindle, not just the washer.
• Reinsert the spindle, tighten it, and check that the tap now closes completely.

How to Prevent Tap Dripping in the Future

Some causes of dripping are natural wear and tear that cannot be entirely avoided, but by following several simple steps, you can significantly extend the lifespan of your tap.

• Avoid moving the tap lever with excessive force – a gentle movement is always better for the cartridge than an abrupt full turn.
• If your water is very hard, consider installing a water filter or an anti-limescale device for the entire house, which will reduce limescale build-up in all taps and appliances simultaneously.
• Regularly clean the tap aerator of limescale, as a clogged aerator increases pressure on the cartridge.
• Have your water pressure checked once a year, especially if you live in an area where central water supply often fluctuates.
• When buying a new tap, choose a reputable manufacturer whose cartridges are widely available even years later – this simplifies future repairs.

When is it Sensible to Call a Plumber?

While most dripping tap issues can be resolved independently, there are situations where it's advisable to call an experienced professional.

• If you are unsure which cartridge or spare part suits your tap, or if the tap is an unusual model or very old.
• If dripping continues after replacing the cartridge or washer, and you suspect a problem with the piping or water pressure.
• If the tap body itself is cracked, fractured, or leaking from connection points, not just the spout.
• If the isolation valves are seized or leaking, making safe DIY repair difficult.
• If you live in an apartment block and the problem might be related to the building's communal water system, not just your own tap.

Summary: Three Most Common Causes

If your tap drips after shutting off the water, first check for the three most common causes – these cover most cases.

• The ceramic cartridge is worn, scratched, or clogged with limescale – replace the cartridge or clean it thoroughly.
• The rubber washer or O-ring has hardened or cracked – replace the washer; it's a cheap and easy fix.
• Water pressure in the house is too high – have a specialist measure the pressure and consider installing a pressure reducer.