How to Use a Plunger Properly on a Blocked Drain

A plunger is one of the simplest tools you can use to clear a minor household blockage. However, it will only work effectively when you use the correct type, create a proper seal and follow the right technique.

Aggressive plunging can splash dirty water, damage seals or push solid objects further into the drainage system. This guide explains how to plunge sinks, toilets, baths and showers safely.

How Does a Plunger Work?

A plunger uses pressure and suction to move water backwards and forwards inside a pipe. This movement can loosen soft blockages caused by:

• Hair
• Soap residue
• Food particles
• Light grease buildup
• Excessive toilet paper

A plunger will not repair damaged pipework or reliably remove tree roots, hard objects or blockages located deep inside a main drain.

Which Type of Plunger Do You Need?

Flat-cup plunger

A flat rubber cup is designed for level surfaces and is suitable for:

• Kitchen sinks
• Bathroom sinks
• Baths
• Some shower drains

The cup must sit flat over the plughole to create an airtight seal.

Flange toilet plunger

A toilet plunger has an extended rubber section that fits into the toilet outlet.

Its shape creates a stronger seal inside a curved toilet bowl. A standard flat sink plunger is usually less effective on a toilet.

Keep separate plungers for sinks and toilets for hygiene reasons.

What to Do Before Plunging

Before starting:

1. Put on waterproof gloves.
2. Remove visible hair or food from the plughole.
3. Take out the sink stopper or drain cover.
4. Remove excessive standing water.
5. Keep towels nearby to catch splashes.
6. Check whether chemical cleaner has been used.

Do not plunge a drain containing strong chemical cleaner. The pressure may cause the product to splash onto your skin or into your eyes.

How to Plunge a Kitchen or Bathroom Sink

1. Cover the overflow opening

Most sinks have an overflow opening near the top of the basin. Air can escape through this opening and prevent the plunger from creating effective pressure.

Cover the overflow firmly with a folded damp cloth. If you have a double sink, seal the second plughole as well.

2. Add enough water

Add enough water to cover the edge of the rubber cup. Water transfers the plunging pressure into the pipe more effectively than air.

3. Position the plunger

Place the cup directly over the plughole. Keep the handle upright and press down gently until the cup forms a complete seal.

4. Begin slowly

Use one or two gentle movements first to release trapped air without splashing water.

5. Use controlled movements

Push down and pull up repeatedly while keeping the cup sealed against the sink.

Use steady, controlled movements rather than excessive force. The pulling action is important because it can draw the obstruction back towards the plughole.

6. Check the flow

After 15–20 seconds, remove the plunger and check whether the water drains.

Repeat the process once if the flow has improved but remains slow. Stop if there is no change.

How to Plunge a Toilet

1. Stop flushing

If the water is rising, do not flush again. Another flush could cause the toilet to overflow.

Wait for the water level to fall. If necessary, remove some water using a suitable container.

2. Use a toilet plunger

Position the flange inside the toilet outlet and ensure the rubber cup is covered by water.

3. Remove trapped air

Press down gently at first. A plunger filled with air may compress suddenly and cause splashing.

4. Plunge steadily

Use several controlled movements while maintaining the seal. Avoid hitting the porcelain with the handle.

5. Test carefully

Once the water begins to drain, pour a small amount of clean water into the bowl before attempting a normal flush.

Stop if the level rises again.

How to Plunge a Bath or Shower

Remove visible hair and clean the drain cover before using a plunger.

For a bath, seal the overflow opening with a damp cloth. Add enough water to cover the plunger cup and use the same controlled technique as for a sink.

A plunger needs a flat surface to create a seal. It may not work on some shower drains because of the shape of the cover or tray.

Do not use excessive force on lightweight acrylic baths or shower trays.

Common Plunging Mistakes

Leaving the overflow open

An open overflow allows pressure to escape and significantly reduces the effectiveness of plunging.

Using the wrong plunger

A flat plunger works best on sinks and baths, while a flange plunger is designed for toilets.

Plunging without water

The rubber cup should be covered by water. Plunging air is less effective and can cause splashing.

Using excessive force

Hard plunging can damage seals, loosen pipe connections or create a mess without removing the blockage.

Plunging after adding chemicals

Chemical drain cleaner may splash back and cause burns or eye injuries.

Repeatedly plunging a recurring blockage

A blockage that continually returns may indicate a deeper obstruction, poor pipe alignment, roots or damaged drainage.

When Should You Stop Plunging?

Stop and contact a drainage professional if:

• The blockage has not improved after several controlled attempts
• Water is backing up through another fixture
• Several drains are affected
• An outside drain is overflowing
• Sewage is present
• The blockage repeatedly returns
• You suspect a solid object is trapped
• You hear persistent gurgling
• There is a strong sewage smell
• You suspect damaged pipework

Continuing to plunge may push a solid object deeper or place unnecessary pressure on already damaged pipes.

What If the Plunger Does Not Work?

The obstruction may be located further inside the pipe or may be too solid to move with household equipment.

Possible causes include:

• Hardened grease
• Wet wipes
• Sanitary products
• A foreign object
• Tree roots
• A collapsed or displaced pipe
• A blockage in a shared drain

Professional drain-clearance equipment can locate and remove deeper obstructions. A CCTV drain survey may be recommended when the cause is unclear or the blockage repeatedly returns.

How Can You Prevent Future Blockages?

Simple habits can reduce the need for plunging:

• Use strainers in kitchen sinks
• Fit hair catchers in showers and baths
• Never pour cooking fat down the sink
• Only flush toilet paper
• Remove visible hair regularly
• Keep food waste out of plugholes
• Investigate slow drainage early
• Avoid putting small objects near open drains

Need Help With a Blocked Drain?

A plunger can resolve a minor blockage near a plughole, but it cannot fix every drainage problem.

If plunging has not restored the flow or the blockage keeps returning, Better Drains can identify and clear the underlying cause using professional drain-clearance and inspection equipment.

Contact Better Drains for reliable help with blocked sinks, toilets, showers and underground drains.

Frequently Asked Questions

How long should you plunge a sink?

Use controlled movements for approximately 15–20 seconds, then check the flow. Stop after several attempts if there is no improvement.

Should you push or pull a plunger?

Both movements are important. Pushing creates pressure, while pulling creates suction that may draw the blockage back towards the plughole.

Why should you cover the sink overflow?

Covering the overflow prevents air and pressure from escaping, allowing the plunger to work more effectively.

Can you plunge a drain after using chemicals?

No. Plunging may cause chemical cleaner to splash onto your skin or into your eyes.

Why does the blockage keep returning?

Recurring blockages may indicate buildup deeper inside the pipe, a foreign object, tree roots or damaged drainage.