How to Unblock a Shower Drain

Most people can do this in about 15 minutes. The six methods below start with the simplest and move up, so you only escalate if you need to.

Why Is My Shower Draining Slowly or Not at All?

A shower waste is a narrow pipe (usually 40mm) with a trap, the U-shaped or bottle-shaped bend that holds water to stop smells coming up. That trap is where almost every blockage forms.

The usual causes:

• Hair. The number one cause. It wraps around the crossbars of the drain cover and the first section of pipe, then catches soap.
• Soap scum. Soap bars and some body washes contain fats that bind with minerals in the water to form a waxy film. Hair sticks to it like glue.
• Limescale. London has hard water. Over time, scale narrows the pipe and gives hair more to snag on.
• Shampoo, conditioner and body-scrub residue. Exfoliating products with grains or oils add to the build-up.
• Foreign objects. Razor caps, cotton buds, and small toy pieces in family bathrooms.
• Pipe problems. A poor fall (gradient), a collapsed section, or a joint that has shifted. These are common in older properties and in showers that were added in a conversion.

Professional observation: a slow drain is a warning, not a nuisance. Shower drains rarely go from fine to fully blocked overnight. If water has been pooling around your ankles for weeks, the blockage has been building for months.

What You’ll Need

Most of this is already in your home:

• Rubber gloves
• Small screwdriver (to lift the drain cover)
• Torch
• Cup plunger (the flat-bottomed type, not a toilet plunger)
• Plastic drain-clearing tool (a thin barbed strip, around £1-£3 from a hardware shop)
• Old toothbrush or bottle brush
• Washing-up liquid
• White vinegar and bicarbonate of soda (optional)
• A bucket and a wire coat hanger (last resort only; see the warning below)

Method 1: Remove the Visible Blockage by Hand

Best for: slow drains where you can see hair on the cover.

1. Remove the drain cover. Some lift off; others have a central screw.
2. Shine a torch into the waste and look for hair or debris.
3. Pull out what you can with gloved fingers or the plastic drain tool.
4. Wipe the cover and the visible rim with a brush.
5. Run the shower for a minute and check the flow.

This fixes more blockages than people expect. Hair collects at the top of the waste, where you can physically reach it.

Method 2: Hot Water and Washing-Up Liquid

Best for: soap-scum build-up with little visible hair.

1. Pour a generous squirt of washing-up liquid into the drain.
2. Boil a kettle and let it cool for about a minute.
3. Pour the hot water slowly down the drain.
4. Repeat once if needed.

Do not use fully boiling water on a plastic waste or a shower tray with plastic fittings, or on older pipes with weakened joints. Very hot water can soften or warp plastic and loosen seals. Hot tap water or just-off-the-boil water is safer and does the job on soap.

Method 3: Plunge It

Best for: blockages just beyond the cover that hand-clearing didn’t shift.

1. Remove the drain cover.
2. Fill the tray with 2-3cm of water so the plunger can create a seal. If the tray is empty, the plunger only moves air.
3. Place a damp cloth over any overflow opening if your shower has one (some trays and baths do).
4. Place the plunger fully over the waste and push down and pull up firmly 10-15 times without breaking the seal.
5. Lift off and see if the water drains.

Common mistake: using a toilet plunger. Its flange doesn’t seal on a flat shower tray, so it does little.

Method 4: Bicarbonate of Soda and White Vinegar

Best for: mild scum and odours. It’s a maintenance method more than an unblocking one.

1. Pour about half a cup of bicarbonate of soda into the drain.
2. Add half a cup of white vinegar. It will fizz.
3. Leave for 15-30 minutes.
4. Flush with hot water.

Honest expectation: this will not dissolve a solid mat of hair. The fizzing action helps loosen soap film, but a hair blockage needs to be physically removed. If methods 1-3 failed, this one probably won’t succeed on its own. Treat it as a freshening step afterwards.

Method 5: Use a Drain-Clearing Tool or Drain Snake

Best for: a hair blockage further down the trap or waste pipe.

1. Remove the cover.
2. Push a plastic barbed strip or a small hand-crank drain snake down the waste.
3. Twist gently as you go. When you feel resistance, work the tool back and forth to hook the blockage.
4. Pull the tool out slowly. Expect a grim clump of hair.
5. Repeat until it comes out clean, then flush with hot water.

Be gentle. A shower trap has tight bends, and forcing a rigid tool can scratch plastic pipe or push the blockage deeper.

Why a wire coat hanger is a last resort: it scratches pipework (creating spots for new build-up), can puncture a flexible waste, and often pushes hair further in rather than catching it.

Method 6: Dismantle the Trap (If You’re Confident)

Best for: a blockage you can’t reach from above, where you can access the pipework underneath.

This applies mainly to showers with an accessible waste, for example over a ceiling void or a utility room. Many modern shower trays are boxed in or sit on a raised plinth, which makes access hard.

1. Put a bucket under the trap.
2. Unscrew the trap carefully by hand. It should come away without tools.
3. Empty and clean the trap, removing hair and sludge.
4. Check the seal and refit, hand-tight only.
5. Run water and check for leaks.

If you can’t see or reach the trap, or the connection looks corroded or loose, stop here. A leaking joint under a shower can damage ceilings and floors quickly.

What Not to Do

Avoid	Why
Caustic or “heavy duty” chemical drain cleaners	They can damage pipes and seals, sit in a blocked trap where they can splash back at you, and are hazardous to skin and eyes. They also make life harder and riskier for the plumber who arrives afterwards.
Mixing different drain cleaners, or cleaners with bleach	Can release toxic gases.
Fully boiling water on plastic	Can warp the waste or loosen joints.
Forcing rigid tools	Risks scratching or cracking the pipe.
Ignoring a persistent slow drain	Residue keeps building and the blockage gets worse and more expensive.

The Health and Safety Executive’s guidance on household chemicals is to read labels, never mix products, and keep rooms ventilated. If you use any shop-bought cleaner, follow the manufacturer’s instructions exactly.

How to Tell if It’s More Than a Shower Blockage

A blocked shower drain is a local blockage: the problem is in the trap or the pipe immediately after it. These signs point somewhere deeper:

• Water also backs up in the sink, bath or toilet when the shower runs, or gurgles when you flush.
• Several fixtures drain slowly at once.
• Water appears in a floor drain or shower from another fixture.
• A persistent sewage smell that returns after cleaning.
• You’ve cleared the waste but the water still sits.

These suggest a blockage in the main branch drain, a defect in the pipe, or a problem further along. DIY tools at the shower won’t reach it. You need drain rods, a high-pressure water jet, or a CCTV drain survey to see what’s happening.

Who is responsible? In general, a blockage inside your property or within the private pipes serving only your home is the owner’s responsibility. A blockage in a public sewer is the water company’s. In London, that is usually Thames Water, though some areas are served by other providers. If you’re unsure which applies, a plumber can tell you after a quick investigation. Check your water company’s website for current guidance on responsibility for drains and sewers.

When to Call a Plumber for a Blocked Shower Drain

Call a professional if:

• You’ve tried methods 1-5 and the shower still won’t drain
• The blockage keeps returning within days or weeks
• More than one fixture is affected
• There’s a smell that doesn’t go away
• You see water leaking from beneath the tray or through a ceiling below
• It’s a wet room with a linear or channel drain
• You live in a flat and the blockage might be in a shared stack
• You manage rental or commercial property and need a recorded, documented fix

What an engineer does differently: instead of guessing, they identify where the blockage is, clear it with the right equipment (drain rods, a drain snake with a cutting head, or a pressure jet), and test the flow afterwards. If the cause isn’t obvious, a CCTV drain survey shows whether there’s a collapsed pipe, root ingress, a bad gradient or a recurring build-up point. That tells you whether it’s a one-off or a defect to repair.

OnTime Plumbers is a local London plumbing and heating company that handles blocked shower drains, bathroom drainage problems and emergency call-outs across Greater London. Our drainage services page explains what we cover and how we work. If your shower has stopped draining completely, or water is coming back up elsewhere, call us or book online. We operate 24/7 for emergencies, with arrival times that depend on your location and demand at the time of the call.

For Landlords, Property Managers and Commercial Premises

Blocked shower drains cause different problems depending on the building.

Rental properties. A slow shower is a common tenant complaint and a common dispute over who pays. Generally, tenants are responsible for damage they cause and for reporting problems promptly. Landlords are responsible for the condition of the plumbing and drainage. Check your tenancy agreement and keep a record of reports and repairs. A plumber’s written job report helps if there’s a dispute.

Gyms, salons, hotels and leisure facilities. High usage means hair and product residue build up faster, so blockages are frequent. A planned drain-cleaning schedule is cheaper than repeated emergency call-outs and avoids closing facilities.

Flats and shared buildings. If neighbouring flats report similar problems, the issue may be in a shared stack. That needs professional diagnosis and, often, coordination with the freeholder or managing agent.

Practical tip for managers: fit a hair catcher in every shower in rental stock. It’s a very low-cost item that prevents most call-outs.

How to Stop Your Shower Drain Blocking Again

Prevention is cheap compared with call-outs:

1. Fit a hair catcher over the drain. Empty it after each use or each day.
2. Remove hair from the cover weekly. It takes 30 seconds.
3. Flush with hot water after showers to move soap residue along.
4. Use liquid soap rather than bar soap where you can, as bar soap leaves more scum.
5. Descale periodically if you live in a hard-water area, using a product suitable for your waste and tray material.
6. Don’t wash pet hair, sand or paint residue down the shower.
7. Act on slow drainage straight away. A 15-minute job now avoids a flooded bathroom later.

What Does It Cost to Unblock a Shower Drain in London?

Costs vary with the type of blockage, access, time of day and whether the work is an emergency. As a general guide, a simple shower blockage is typically cheaper than a deeper drain blockage that needs jetting or a CCTV survey. Out-of-hours and emergency visits usually cost more than scheduled appointments.

Ask any plumber for a clear explanation of the call-out fee, what’s included, and whether the price changes if the problem is more complex than it looks.

Frequently Asked Questions

How do I unblock a shower drain without chemicals?

Remove the cover, pull out visible hair, then use a plunger or plastic drain tool. Flush with hot water and washing-up liquid. This clears most hair-and-soap blockages without any chemicals.

Why is my shower water not draining?

The most common cause is a plug of hair and soap scum in the trap just below the drain cover. Less often, there’s a deeper blockage, a pipe defect or a problem in the shared drain. If other fixtures are also slow, the issue is deeper than the shower.

Does bicarbonate of soda and vinegar unblock a shower drain?

It can freshen the drain and loosen light soap film, but it won’t dissolve a solid mass of hair. Physically removing the blockage works better.

Can I use boiling water to unclog a shower drain?

Use hot, not fully boiling, water. Boiling water can damage plastic waste pipes and soften joints. Just-off-the-boil water or hot tap water is safer.

Is it safe to use drain cleaner in a shower?

Chemical drain cleaners can damage pipes, cause splashes and release harmful fumes if mixed. Many plumbers recommend avoiding them and removing the blockage mechanically. If you do use one, follow the label strictly and never mix products.

How long does it take to unblock a shower drain?

A simple hair blockage takes about 10-20 minutes to clear yourself. A professional visit for a straightforward shower blockage is usually quick, but deeper blockages or those needing a CCTV survey take longer.

Why does my shower drain keep blocking?

Repeated blockages usually point to build-up in the pipe, a poor gradient, a damaged section, or a shared stack issue. If you’ve cleared it several times and it returns, ask a plumber to inspect it.

My shower drain smells. Is it blocked?

A smell can come from decomposing hair and soap in the trap, a dried-out trap, or a drainage problem. Clean the cover and trap first. If the smell persists, have it checked.

Who is responsible for a blocked drain, me or the water company?

Generally the property owner is responsible for drains serving only their property. The water company handles public sewers. A plumber can often tell you which applies.

Can I unblock a shower drain myself in a flat?

You can try the same methods at the shower. If neighbours report problems, or other fixtures are affected, the issue may be in a shared pipe, and you should contact your landlord or managing agent.

When should I call an emergency plumber for a blocked shower?

Call straight away if water is backing up into other fixtures, leaking through ceilings, or there is a strong sewage smell, as these can signal a wider drain failure or water damage risk.

Need Help With a Blocked Shower Drain in London?

If you’ve tried the steps above and your shower is still not draining, OnTime Plumbers can help. Our engineers diagnose the cause, clear the blockage and tell you plainly whether it’s a one-off or a sign of a bigger problem.

Call us on [PHONE NUMBER] or book an appointment. For emergencies, we’re available 24/7.