Potential health risks from unused hot water tap
A disused hot water tap behind a washing machine can leave stagnant, lukewarm water trapped in the pipework – ideal conditions for Legionella bacteria to grow. The domestic risk is low, but it is easily eliminated by fitting a blanking cap to the unused tap or having the redundant pipework removed by a plumber.
Temperature range in which Legionella bacteria multiply most rapidly
Almost all washing machines sold in the UK today use a single cold-water supply
A blanking cap on the unused hot tap costs very little and eliminates the risk
Why Does an Old Hot Water Tap Create a Health Risk?
Decades ago, washing machines in the UK commonly used both a hot and a cold water supply. Homes were plumbed accordingly, with a dedicated hot tap installed alongside the cold one behind the machine.
Modern washing machines are cold-fill only. They draw cold water and heat it internally, so the hot tap is no longer connected or used. The problem is what happens inside the pipework when that tap sits idle.
Legionella pneumophila is a naturally occurring bacteria found in water. It multiplies rapidly in warm, stagnant water between 20°C and 45°C, and can cause Legionnaires’ disease – a potentially serious form of pneumonia – if contaminated water droplets or aerosols are inhaled. The UK Health Security Agency (UKHSA) and the HSE both identify stagnant pipework as a contributing risk factor.
A disused tap that remains connected to the hot water supply creates what plumbers call a dead leg – a section of pipe with no regular water flow. The water inside stagnates, settles at a lukewarm temperature, and creates the exact conditions in which Legionella can take hold.
How Does the Risk Arise With a Washing Machine Specifically?
The typical scenario is straightforward. A cold-fill washing machine is installed and connected to the cold tap. The old hot tap is turned off and forgotten. No one uses it – but it remains connected to the hot water system through a short section of pipe inside the wall.
That section of pipe never flushes. The water inside it sits at an intermediate temperature for weeks, months, or years. If the tap is ever accidentally opened – during a house move, a repair visit, or a routine check – there is a risk of dispersing bacteria into the air.
| Scenario | Risk Level | Why |
|---|---|---|
| Hot tap in regular use, water flowing freely | Very low | Regular flow prevents stagnation |
| Hot tap turned off but still connected to supply | Low–moderate | Dead-leg pipework can harbour bacteria over time |
| Hot tap capped off with a blanking cap | Very low | No pathway for stagnant water or aerosol dispersal |
| Redundant pipework fully removed by a plumber | Eliminated | No dead-leg pipework remaining |
How Serious Is the Risk in a Domestic Home?
It is important to keep this in perspective. Legionnaires’ disease is predominantly associated with large, complex water systems – cooling towers, hotel plumbing, hospital water supplies, and commercial buildings. The HSE acknowledges that the risk in a typical private home is low.
A single disused domestic tap does not carry the same risk as a commercial water system. However, the risk is not zero, and the fix is simple enough that there is no good reason to leave it unaddressed.
“Water systems in domestic premises present a low Legionella risk, provided basic precautions are taken. Flushing out infrequently used outlets regularly is a straightforward and effective control measure.”
— Health and Safety Executive (HSE), Legionella Guidance for Domestic Premises
Higher-risk individuals
Older adults, smokers, people with weakened immune systems, and those with chronic lung conditions are more susceptible to Legionnaires’ disease. If anyone in the household falls into one of these groups, acting promptly is particularly advisable.
What Should You Do About an Old Hot Water Tap?
There are two practical solutions depending on your situation and budget. Both are far preferable to simply leaving the tap turned off and forgotten.
Option 1: Fit a Blanking Cap
A blanking cap screws or pushes onto the tap outlet, sealing it completely. This prevents the tap from being accidentally opened and removes any risk of aerosol dispersal. Blanking caps are inexpensive and the job takes minutes.
Option 2: Remove the Pipework
A qualified plumber can isolate and remove the redundant hot water pipework entirely. This eliminates any dead-leg pipe inside the wall and is the definitive, permanent fix – especially recommended if the pipework runs any significant distance.
Need a hand with your washing machine?
If you’re not confident working around your plumbing or water supply, a qualified engineer can help. Book a repair visit or find the parts you need using the links below.
What if My Machine Is Already Connected to Cold Only?
If your washing machine is connected solely to the cold tap – which is the case for almost all modern machines – then the hot tap behind the machine is entirely redundant. Simply having it turned off is not sufficient.
Cap off the old hot tap using a blanking cap, or ask a plumber to remove the pipework. See our guide on converting a hot-and-cold fill machine to cold-only supply for full details on managing this transition.
Does It Matter if the Hot Tap Is Still Being Used?
If your washing machine is actively using the hot water supply – as some older twin-fill machines do – then water flows through the tap with every wash cycle. Regular flow significantly reduces the risk of stagnation and bacterial growth.
That said, very few washing machines sold in the UK today use a hot fill. Check the back of your machine: cold-fill-only models have a single inlet hose connection. Twin-fill machines have two – one marked hot, one marked cold.
Can You Connect a Cold-Fill Machine to the Hot Tap?
Some people wonder whether feeding a cold-fill machine with hot water could improve washing performance or reduce energy consumption. Whitegoods Help does not recommend this.
Why it’s a bad idea
- Cold-fill machines are calibrated to heat water from cold – feeding them hot water disrupts temperature sensing
- It can cause wash performance problems and damage internal components
- It may invalidate your manufacturer’s warranty
What to do instead
- Connect the machine to the cold water supply only
- Cap off or have a plumber remove the old hot tap
- Let the machine manage water heating as designed
For a full explanation, read our guide: Can you connect a cold-fill washing machine to the hot tap?
What to Check Behind Your Washing Machine
Not sure what you have? Follow these steps to assess the situation quickly.
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Pull out the machine slightly and look at the water connections at the rear. Count the number of inlet hoses – one means cold-fill only, two means hot-and-cold fill.
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Locate all taps on the wall. If there are two taps (one cold, one hot) but only one hose connected to the machine, the hot tap is redundant.
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Check whether the hot tap is open or closed. If open but unconnected, close it immediately. Either way, it should be capped off.
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Fit a blanking cap to the hot tap outlet, or contact a plumber to remove the dead-leg pipework entirely. See our guide to blanking off the hot tap for full instructions.
Any work involving your home’s hot water pipework should be carried out by a qualified plumber. Do not attempt to cut or modify pipework yourself unless you are fully competent to do so. If you have broader concerns about Legionella risk in your water system – particularly in larger or older properties – contact a water hygiene specialist. The HSE provides free Legionella guidance for domestic properties, including landlord responsibilities. Landlords have a legal duty of care under the Health and Safety at Work Act 1974 to assess and control Legionella risks.
Related Guides
Frequently Asked Questions
Can a washing machine cause Legionnaires’ disease?
A washing machine itself is not a source of Legionella. The risk comes from stagnant water sitting in a disused hot water tap or dead-leg pipe that remains connected to the hot supply behind the machine. If that water is disturbed and aerosolised, there is a theoretical inhalation risk. In practice, domestic risk is considered low, but capping off unused hot taps removes it entirely.
What is a dead leg in plumbing?
A dead leg is a section of pipe connected to the water supply with no regular flow through it. Water stagnates inside, and if the pipe is part of the hot water system, it can settle at temperatures between 20°C and 45°C – the ideal range for Legionella bacteria to multiply. Dead legs are a recognised risk factor in both commercial and domestic water systems.
How do I know if my washing machine uses hot and cold fill?
Check the back of your machine. A cold-fill-only machine has a single inlet hose connection, usually marked with a blue label or the word “cold”. A hot-and-cold-fill machine has two connections – one for hot, one for cold. The vast majority of washing machines sold in the UK since the early 1990s are cold-fill only.
Is it safe to just turn off the old hot tap and leave it?
Turning the tap off is better than leaving it open, but it does not fully resolve the issue. The section of pipe between the closed tap and the main hot water supply can still hold stagnant water. Fitting a blanking cap to the tap outlet – or having the pipework removed – is the proper fix.
Can I connect my cold-fill machine to the hot tap to save energy?
This is not recommended. Cold-fill machines are designed and calibrated to heat water from cold. Feeding them a hot water supply can interfere with temperature sensing, compromise wash performance, damage internal components, and may invalidate the manufacturer’s warranty. Connect cold-fill machines to the cold supply only.
Who is responsible for Legionella risk in a rented property?
Landlords have a legal duty of care under the Health and Safety at Work Act 1974 and the associated Approved Code of Practice (L8) to assess and control Legionella risks in rental properties. This includes identifying and addressing dead-leg pipework. Tenants who suspect a risk should report it to their landlord in writing. The HSE’s guidance covers landlord responsibilities in full.
Using a washing machine from storage
Before using a washing machine that has been in storage – especially for an extended period – there are several checks to carry out first. Even a machine that worked perfectly before being stored can develop faults while unused. Do not assume it will be fine without testing it carefully.
A machine that has been stored for a long time may leak, flood, or develop other faults during its first use. Never leave it unattended until you are confident it is working correctly.
Why Does Storage Cause Problems?
Appliances can develop faults during long periods of non-use. Rubber seals and hoses can dry out, harden, crack, or split – particularly if stored in a cold, damp, or poorly ventilated environment. The water pump can seize if it has not been used for an extended time. Other components can corrode or deteriorate in ways that are not visible from the outside.
This is not always predictable – components that appear fine can fail on first use. The checks below are designed to catch the most common issues before they cause water damage or a bigger problem.
Step 1: Check the Pump Before Letting Any Water In
The most important first check is whether the water pump is working. If the pump has seized and water enters the machine, it cannot be pumped out – leaving a machine stuck full of water. Avoid this by running a spin cycle first, before any water is introduced.
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Set the machine to a spin-only cycle with no laundry inside. Do not add water at this stage.
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Listen carefully during the spin. There should be two distinct sounds: the motor and drum spinning together, and the water pump running. Most washing machines make a recognisable pump sound – a consistent whirring or humming noise separate from the drum rotation.
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If only one sound can be heard and there is no pump sound, or if there is only a loud humming from beneath the machine, the pump may have seized. Do not allow water into the machine until the pump has been freed or replaced. See: washing machine stuck full of water.
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If the pump sounds like it is running normally, allow the machine to complete the full spin cycle. If it completes without issue, proceed to Step 2.
Step 2: Inspect Seals and Hoses
Before allowing any water in, visually inspect the door seal and any hoses visible inside the machine. The sump hose – which runs from the outer drum down to the pump – is particularly prone to deterioration if the machine has been stored in poor conditions. Look for cracks, hardness, or any signs of splitting.
If the seals and hoses look intact, proceed. If they look damaged or very dry, they may need replacement before the machine is used.
Step 3: First Water Fill – Watch Carefully
Start a wash cycle and allow the machine to fill with water. Stay present throughout and watch for two things:
Watch for leaks
Water on the floor at any point means there is a leak. Stop the cycle immediately and diagnose the cause before continuing. See: troubleshooting a leaking washing machine.
Watch for overfilling
If the water level rises above halfway up the door glass and shows no sign of stopping, the machine may be overfilling. Stop the cycle. See: washing machine overfilling.
If the machine fills to a normal level and begins washing without leaking, that is a good sign. At this point, cancel the wash cycle and immediately run a spin to confirm the pump can remove the water successfully.
Step 4: Confirm the Pump Can Drain
Cancel the wash cycle with water in the drum and switch to spin only. Confirm that the water drains out completely and without hesitation. If it drains successfully, the machine has passed its basic checks.
Step 5: Run a Full Test Cycle Under Supervision
Set the machine to a 40°C cottons programme and run a full cycle. Do not leave the machine unattended. A machine may not leak immediately but can develop a leak later in the cycle – during a rinse, during spin, or as hoses warm up and internal pressure changes.
- Stay with the machine for at least the first 10 minutes without any issues before moving away.
- Return to check it every few minutes throughout the cycle – particularly at the start of each rinse and spin phase.
- If it completes the full cycle without incident, continue to monitor it for the next two or three wash cycles before leaving it to run unattended.
- If any leak, flooding, or unusual behaviour occurs, stop the machine and diagnose the fault before using it again.
Related guides
Frequently Asked Questions
Can a washing machine develop faults while it’s in storage?
Yes. Rubber seals and hoses can dry out, harden, crack, or split during extended storage – particularly in cold, damp, or poorly ventilated conditions. The water pump can also seize if unused for a long time. Even a machine that was working perfectly before storage can develop faults during the period of non-use, sometimes without any visible warning signs on the outside.
Why should I check the pump before letting water in?
If the pump has seized during storage and cannot run, water that enters the machine cannot be pumped out. This leaves the drum full of water with no easy way to remove it. Running a spin cycle with no water first allows you to confirm the pump is working before any water is introduced to the machine.
What does a seized washing machine pump sound like?
During a spin cycle, a working machine produces two sounds – the drum and motor spinning, and the water pump running. If only the drum and motor can be heard with no pump sound, or if there is a loud humming from beneath the machine without the drum spinning, the pump may have seized. A pump that has seized will need to be freed or replaced before the machine can be used.
How long should I supervise a washing machine after getting it out of storage?
Stay with the machine throughout the entire first cycle, checking it every few minutes – particularly at the start of each rinse and spin phase. A leak may not appear immediately and can develop later in the cycle as hoses warm up and pressure changes. Continue to monitor it for the next two or three wash cycles before leaving it to run unattended.
What should I do if the machine leaks on first use after storage?
Stop the machine immediately and do not use it again until the source of the leak has been identified and resolved. See: troubleshooting a leaking washing machine. Common causes after storage include a dried-out door seal, a split sump hose, or a deteriorated pump seal.
Transporting a washing machine – How to store a washing machine
How to connect a washer or dishwasher properly
Waste water from washing machines and dishwashers must drain into the sewerage system – not the surface water or storm drain system used by gutters and rainwater downpipes. Connecting to the wrong drain is illegal and environmentally harmful. This article covers how to identify correct connections and what misconnection looks like.
Washing machines and dishwashers must be connected to the correct drainage system. Misconnection to the wrong drain is a significant and widespread problem that sends soapy waste water directly into rivers and streams rather than the sewerage system where it belongs.
It may help to read Part 1: Is your washing machine or dishwasher misconnected? first for context.
Connecting a Washing Machine or Dishwasher Correctly
Connection Diagram 1 – Correct and Incorrect Connections
Diagram showing correct and incorrect plumbing connections
In the diagram above, the house on the left has all plumbing connected correctly. Water from gutters (shown in blue) runs through the storm drain system and into rivers. Waste water from the toilet, bath, sinks, and appliances (shown in red) runs into the sewerage system.
The house on the right is misconnected – two appliances are draining into the same drain that the gutter water uses, marked with red crosses. This means detergent-laden waste water flows directly into the storm drain system and from there into rivers and streams.
Connection Diagram 2 – How Connections Should Be Made
How appliance drain connections should be made
Two Real-Life Examples of Misconnected Plumbing
Real examples of appliance waste pipes incorrectly connected to rainwater drain systems
The left side of the image shows an appliance or sink waste pipe emerging from an upstairs wall and connecting into the clean rainwater drain pipe for the guttering. The right side shows the same problem occurring downstairs – most likely a washing machine plumbed in using the nearest available drain connection, which happened to be the wrong one.
This type of misconnection is easy to make accidentally, particularly when plumbing in a washing machine in a location where the nearest drain access point leads to the surface water system rather than the foul water sewer.
Part 1: Is your washing machine or dishwasher misconnected? – How to install a washing machine
Frequently Asked Questions
Which drain should a washing machine connect to?
A washing machine must connect to the foul water sewer – the same drain that takes waste from toilets, baths, and sinks. It must not connect to the surface water or storm drain system, which carries rainwater from gutters and downpipes directly to rivers and streams without treatment.
How do I know if my washing machine is misconnected?
The most reliable way is to run the machine and check which external drain the water exits from. Water leaving via a drain connected to a downpipe or surface water gulley is a sign of misconnection. See: is your washing machine or dishwasher misconnected?
Is it illegal to misconnect a washing machine drain?
Yes. Connecting appliance waste water to the surface water drain system is illegal under UK water regulations and environmental law. Detergent-laden waste water discharged to rivers causes significant environmental harm. If a misconnection is identified, it should be corrected as soon as possible.
What’s the best way to pull a washing machine out?
Open the door, grip the top of the door seal opening, lift the front of the machine slightly, and walk it forward on its back feet. Before pulling, always unplug the machine, turn off the water supply, and check whether the hoses and drain have enough slack – or disconnect them first. Protecting your flooring before you start will save a lot of trouble.
Washing machines are heavy – typically 60 to 90kg. Do not attempt to move one alone if you have any back or joint problems. Always unplug the machine from the mains before moving it. Never pull a washing machine that is still connected to live water or power.
Pulling a washing machine out from under a kitchen worktop is straightforward if done in the right order. The most common mistakes – overstretching a hose, catching the flooring, or damaging the plug socket – are all avoidable with a few minutes of preparation before you start.
Before You Pull: Disconnection Checklist
A washing machine is connected to at least three things that can stop it coming out, damage themselves, or cause a flood if not dealt with correctly. Work through these before moving the machine at all.
Step 1: Unplug the Mains Cable
Unplug the machine at the wall socket before doing anything else. If the socket is behind the machine and you cannot reach it, the cable will need to be fed slack as the machine comes forward – but the machine must be unplugged before it leaves the room or comes into a position where you might pull the plug from the socket under load.
If the cable has been routed through a small hole in a cabinet, you may need to remove the plug to pull the cable back through. Keep the plug and any fixings safe for reassembly.
Step 2: Turn Off the Water Supply
Locate the isolation taps on the water inlet hoses – usually behind or to the side of the machine – and turn them off. If the taps are stiff, use the minimum force needed and support the tap body firmly. Twisting a tap too hard can loosen it from the copper pipe behind.
If the fill hoses are short or under tension, disconnect them before pulling the machine forward. An overstretched fill hose can snap at the point where it connects to the machine. If the water supply is still on when this happens, the result is an immediate flood with no warning.
If either fill hose is at full stretch before the machine has moved, stop and disconnect it before continuing. A snapped fill hose with the water still running will flood the kitchen in seconds.
Step 3: Disconnect the Drain Hose
The drain hose is commonly connected to the U-bend under the kitchen sink. Unscrew the plastic connector and pull the hose free – this is usually straightforward by hand. Once disconnected, feed the hose back through any cabinet holes and towards the machine so it has enough slack to come forward.
If the plastic connector is too wide to pull back through a cabinet hole, twist the hose off the connector and reattach it securely when reconnecting. Make sure the hose is pushed on tightly at both ends after reassembly to prevent leaks.
Once the drain hose is disconnected from the U-bend, any water poured into the sink will flow out through the open connection into the cabinet below. Block the hole with a cloth until the machine is back in position and reconnected.
How to Pull the Washing Machine Out
With everything disconnected and slack, the machine is ready to move.
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Open the washing machine door fully. Grip the top of the door opening with both hands, at the point where the door seal meets the cabinet. This gives a solid, central hold on the machine.
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Lift the front of the machine slightly – at least a centimetre – to free the front feet from the floor and tilt the weight onto the back feet.
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Walk the machine forward by pulling it towards you while keeping the front slightly lifted. The machine should move smoothly on its back feet.
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Once the machine is far enough out to work on, lower it down carefully onto all four feet.
Protecting the Flooring
Washing machine feet can cause serious damage to vinyl, lino, and cushion flooring if the machine is dragged rather than lifted and walked. Before moving the machine, check that the feet are not stuck to the floor – they often bond to soft flooring over time.
Lift the front first to free the front feet, then tip the machine slightly forward to check and free the rear feet. Placing a folded towel or piece of cardboard under the feet before moving gives some protection and helps the machine slide more easily on hard floors.
What If the Flooring Does Not Go All the Way Under?
In many kitchens, the floor covering stops just underneath the washing machine rather than running all the way to the back wall. When the machine is pulled forward, the rear feet drop off the edge of the flooring and catch on the bare floor underneath – which can stop the machine moving entirely, or gouge badly into vinyl or laminate.
If this happens, push the machine as far back as possible, then tilt it forward to lift the rear feet clear of the flooring edge, and walk it forward on the front feet. This requires enough clearance between the top of the machine and the worktop above – if there is no room to tilt, see our guide on appliances stuck behind a tiled or raised floor for further options.
What If the Door Will Not Open?
If the door is locked due to a fault, there are two alternatives for getting purchase on the machine. Removing the soap drawer and gripping through the drawer opening works but is awkward. Lifting from underneath the front of the machine is harder still. With two people, a combination of both can work.
If the machine is also full of water, deal with that first – it adds significant weight and makes the machine much harder to move safely. See our guide on how to drain a washing machine full of water before attempting to move it.
Pushing the Machine Back In
Walk the machine back by pushing one side a little, then the other – this is easier and more controlled than pushing straight back. Push as low down the front panel as possible. Many washing machine front panels are thin and will dent easily under pressure from knees or hands pushing near the middle.
If the machine is hard to push back, it is tempting to use lubricant under the feet – but this can cause the machine to move around during spin cycles. If you do use any lubricant, use the smallest amount possible and only as a last resort.
Once back in position, reconnect the drain hose, fill hoses, and mains plug – then run a short cycle and check everything for leaks before pushing the machine fully back under the worktop. For a full reconnection checklist, see our guide on checks to carry out after installing a washing machine.
Need a Repair or Spare Parts?
If you have pulled your machine out to investigate a fault, Whitegoods Help can help with the next step.
Related Guides
Appliance Stuck Behind a Tiled FloorWhat to do when a washing machine or dishwasher cannot come forward due to tiles or raised flooring at the front.
How to Drain a Washing Machine Full of WaterStep-by-step guide to draining a machine that has stopped mid-cycle before attempting to move or repair it.
5 Checks After Installing a Washing MachineThe checks to run after pushing a machine back into position to confirm everything is correctly reconnected.
Transporting a Washing Machine SafelyHow to prepare a washing machine for transport, including the transit bolt requirement and what to do if you no longer have them.
Frequently Asked Questions
What is the best way to pull a washing machine out from under a worktop?
Open the door and grip the top of the door seal opening with both hands. Lift the front of the machine slightly to tilt it onto the rear feet, then walk it forward. Always disconnect the mains plug, turn off the water supply, and check the hoses and drain have enough slack before you start moving the machine.
Do I need to disconnect the hoses before pulling the machine out?
Not always, but check them first. If the fill hoses or drain hose are short or at full stretch, disconnect them before pulling the machine forward. An overstretched fill hose can snap at the connection point, causing an immediate flood if the water supply is still on.
How do I stop the feet from damaging my flooring?
Lift the front feet free from the floor before pulling, and check the rear feet too – they often bond to soft flooring over time. Placing a folded towel or piece of cardboard under the feet before moving gives protection and makes sliding easier. Never drag the machine without lifting the feet first.
What if the washing machine is stuck and will not come forward?
The most common cause is the rear feet catching on the edge of flooring that does not run all the way to the back wall. Tilt the machine forward to lift the rear feet over the edge and walk it out on the front feet. If there is not enough clearance under the worktop to tilt, see our guide on appliances stuck behind a tiled or raised floor.
How do I pull a washing machine out if the door will not open?
Try gripping through the soap drawer opening as an alternative to the door. If the machine is full of water, drain it first to reduce the weight before attempting to move it. With no door access and no drawer, two people working together – one lifting from each side – is the safest approach.
What should I check when pushing the machine back in?
Reconnect the drain hose, fill hoses, and mains plug before pushing the machine fully back. Run a short cycle and check all connections for leaks while the machine is still accessible. Only push it fully back once you are satisfied everything is tight and leak-free.
Can I install a washing machine in a bathroom?
It is permitted to install a washing machine in a bathroom in the UK, but strict electrical regulations apply. The machine must be positioned so that someone in the bath or shower cannot reach it, the electrical connection must be made outside the bathroom or from a suitably protected source, and the circuit must be RCD protected. Always consult current regulations before proceeding – the rules are specific and must be followed exactly.
Installing a washing machine in a bathroom involves work in a special location under Part P of the Building Regulations. This work must either be carried out by a registered electrician or notified to your local building control authority. Do not attempt this installation without checking the current requirements. Regulations may have changed since this article was written – always verify with a qualified electrician or your local authority.
A bathroom is far from an ideal location for a washing machine – but it is a common solution in smaller homes, flats, and properties without a separate utility room. Understanding the rules before you proceed can prevent both a dangerous installation and a costly building regulations problem.
Why a Bathroom Is Not Ideal
There are two practical concerns with a bathroom installation beyond the electrical regulations.
The first is flood risk. A washing machine installed upstairs in a bathroom that develops a leak or floods – whether from a hose, a pump fault, or an overflow – can cause serious damage to the ceiling and floor structure below. The risk is not eliminated by a careful installation, only managed. An aqua-stop inlet hose reduces the risk of a supply-side flood. See our guide on aqua-stop hoses for more detail.
The second is the bathroom environment itself. Steam and condensation are damaging to the electronic control systems inside modern washing machines. A bathroom that regularly becomes very humid will shorten the life of the machine’s PCB and other sensitive components over time.
What the Electrical Regulations Require
Electrical installations in rooms containing a bath or shower are governed by BS 7671 (the IET Wiring Regulations), specifically Section 701 – Locations Containing a Bath or Shower. These regulations define restricted zones around the bath and shower within which certain equipment cannot be installed or connected.
The regulations are technical and detailed. The summary below covers the key points relevant to washing machine installation, but it is not a substitute for consulting the current regulations or a qualified electrician before proceeding. Regulations are updated periodically and local requirements may vary.
The Key Requirements for Bathroom Washing Machine Installation
- Zone restrictions: The washing machine must be positioned outside Zone 1, which extends 0.6 metres horizontally from the edge of the bath or shower tray. No standard socket outlet can be installed within zones 0 or 1.
- Reachability: The critical test is that a person using the bath or shower must not be able to reach the washing machine. If they can touch it while in contact with water, the installation does not comply.
- Socket location: The plug and socket connection must be located outside the bathroom – typically in an adjacent hallway or airing cupboard – with the cable running through the wall. Standard 13A socket outlets cannot be installed inside a bathroom.
- RCD protection: The circuit supplying the washing machine must be protected by a Residual Current Device (RCD). This is a requirement for all socket circuits in bathrooms and most domestic circuits under current regulations.
- Notifiable work: This installation falls under Part P of the Building Regulations in England and Wales. It must be carried out by a registered competent person or notified to building control.
The requirements outlined above are based on the IET Wiring Regulations 18th Edition (BS 7671:2018 and subsequent amendments). Regulations are updated periodically. Always consult a qualified electrician or your local building control authority to confirm current requirements. You can find your local council at gov.uk/find-local-council.
Do You Need an Electrician?
Yes, in most cases. Installing a socket circuit in a bathroom, or altering an existing circuit to supply a washing machine in a bathroom, is notifiable electrical work under Part P of the Building Regulations. This means it must be carried out by a registered electrician (such as one registered with NICEIC, NAPIT, or a similar scheme) or notified to your local building control authority before the work is done.
Using a registered electrician is the simpler route – they can self-certify the work and issue the necessary certificate without a separate building control application.
Alternatives Worth Considering
Before committing to a bathroom installation, it is worth considering whether there is a more suitable location available. A landing cupboard, a hallway, or even a garage may be workable alternatives that avoid the regulatory complexity and environmental risks of a bathroom installation.
See our guides on installing a washing machine in a garage and installing in a basement for guidance on other non-standard locations.
Need Help With Washing Machine Installation?
For a straightforward installation in a standard location, our guides cover everything from connection to first use.
Related Guides
Can You Put a Washing Machine in a Garage?The practical and technical considerations of a garage installation, including cold weather, damp, and plumbing access.
Installing in a BasementDrainage requirements and pump solutions for machines installed below the main drain level.
Aqua-Stop HosesHow flood-protection inlet hoses work and whether they are worth fitting – especially relevant for upstairs installations.
How to Connect a Washing Machine ProperlyA complete guide to connecting inlet and drain hoses correctly, including standpipe height requirements.
Frequently Asked Questions
Is it legal to have a washing machine in a bathroom in the UK?
Yes, but only if the installation complies with BS 7671 (the IET Wiring Regulations) and Part P of the Building Regulations. The machine must be positioned outside the restricted zone around the bath or shower, cannot be reachable by someone using the bath, and the electrical connection must be made from outside the bathroom on an RCD-protected circuit. The work must be carried out by a registered electrician or notified to building control.
Can I put a socket in a bathroom for a washing machine?
Not a standard 13A socket outlet. Standard sockets cannot be installed within the restricted zones around a bath or shower. The washing machine connection must be made from a socket positioned outside the bathroom – typically in an adjacent hallway or airing cupboard – with the cable running through the wall. A qualified electrician can advise on the correct configuration for your specific layout.
Does a bathroom washing machine need to be on an RCD circuit?
Yes. Any circuit supplying a bathroom location must be RCD protected under current wiring regulations. In modern consumer units, most circuits are already RCD protected – but this should be confirmed by a qualified electrician before the installation proceeds.
How far from the bath does a washing machine need to be?
The machine must be positioned outside Zone 1, which extends 0.6 metres horizontally from the edge of the bath or shower tray. The practical test is that a person using the bath or shower must not be able to reach the machine while wet. If there is any doubt about the distance, the installation does not comply.
What are the risks of having a washing machine in an upstairs bathroom?
The main risks are flood damage if the machine leaks or overflows – water from an upstairs bathroom can cause significant structural damage to floors and ceilings below – and accelerated wear on the machine’s electronics from steam and condensation. An aqua-stop inlet hose reduces supply-side flood risk, but does not eliminate all failure modes.
How to Install a Washing Machine drain hose
The drain hose should be permanently plumbed in – either into a standpipe or via a spigot connector on the U-bend under the kitchen sink. It must never simply be hooked over a sink. Once connected, ensure the hose runs upward by at least 10cm from the connection point before descending to the machine, to prevent backflow from the sink.
This guide covers drain hose installation specifically. For fill hose connection, taps, and the full washing machine installation process, see our washing machine installation guide (Part 1). Always follow the instructions in the machine’s manual – if you do not have one, download a copy from our instruction manual resource.
Why the Drain Hose Must Be Permanently Plumbed In
Hooking the drain hose over a sink edge is not an adequate installation. It is only acceptable as a very temporary arrangement – for example, testing a machine before plumbing in.
Risks of an unsecured drain hose
- A dishcloth or washing up bowl left in the sink can block the drain, causing the sink to overflow
- If the hose falls out of the sink, the machine will flood the room – and continue filling indefinitely trying to compensate for lost water
- The machine is left unattended while flooding – this is how serious water damage occurs
Correct permanent connection
- Into a standpipe with a properly fitted drain hose crook
- Via a spigot connector screwed to the U-bend under the sink
- Either method keeps the hose securely in position regardless of water pressure
Connecting to the U-Bend Under the Sink
Connection to the U-bend under the kitchen sink is now the most common method. It is straightforward, requires no external pipework, and is suitable for most domestic installations.
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Fit the spigot connector to the U-bend. The spigot is a tapered plastic fitting that screws directly onto the U-bend body. Take care not to cross-thread the plastic fitting – hand-tighten until snug, then a quarter turn with pliers. Do not overtighten.
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Push the drain hose firmly onto the spigot. The tapered profile means the hose tightens as it is pushed on. Push it on as firmly as possible until it fits snugly. A hose clip over the connection adds security and is recommended for any permanent installation.
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Check for a blanking piece. On a new-build property or a spigot being used for the first time, there may be a blanking cap inside the connector. This must be removed before the drain hose is connected. See our guide on washing machine won’t drain after moving for more on this.
The Anti-Backflow Loop: Critical Installation Detail
The single most important detail beyond the physical connection is ensuring the drain hose does not run directly downward from the machine to the connection point. If there is a continuous descending run from the machine to the U-bend, water from the sink can travel back down the drain hose and into the washing machine drum – creating a persistent standing water fault that is often misdiagnosed as a machine problem.
The hose should travel upward from the spigot connection by at least 10cm (approximately 4 inches) before descending toward the machine. If the hose naturally runs straight down, secure it up to the underside of the worktop with a cable tie or clip to create the required loop. This prevents sink water from backflowing into the drum.
Drain Hose Too Short?
Factory-fitted drain hoses are typically 1.5 to 2 metres long – enough to reach a standpipe or U-bend directly beside or behind the machine. If the machine needs to be installed further from the drainage point, there are two options:
- Replace the drain hose with a longer aftermarket hose (typically 2 to 2.5 metres). This is the neater option and replaces the original hose entirely.
- Use a drain hose extension kit. A joiner connector allows an additional length of drain hose to be fitted to the original. Ensure the joint is secure and the total hose length does not exceed the maximum specified in the machine’s manual – excessively long drain hoses can reduce pumping efficiency.
Part of a Full Washing Machine Installation?
Related Installation Guides
Won’t Drain After Installation or MovingWhy a newly plumbed washing machine may not drain – including the blanking piece fault and how to fix it.
Machine Fills and Drains SimultaneouslyWhy a machine may fill and drain at the same time after installation – usually a siphoning issue.
Aqua-Stop HosesHow flood-protection inlet hoses work and whether they are worth fitting on your machine.
How to Connect a Washing Machine ProperlyA complete connection guide covering inlet hoses, drain hose, and what to check before first use.
More Installation Guides
Frequently Asked Questions
Can I just hook the drain hose over the sink?
Not as a permanent installation. A hose left unsecured over a sink can fall out during a cycle, flooding the room. The machine will continue filling indefinitely to compensate for the lost water – this is how serious water damage occurs. A blocked sink can also cause overflow. The drain hose must be permanently and securely connected to the plumbing.
Does it matter which way the drain hose runs?
Yes. The hose must not run in a continuous downward slope from the machine to the drain connection. It needs to rise by at least 10cm before descending to the U-bend or standpipe. Without this loop, water from the sink can siphon back into the machine drum. Secure the hose to the underside of the worktop with a clip or cable tie to create and maintain the correct loop.
What if the drain hose is too short to reach the plumbing?
Either replace it with a longer aftermarket hose (typically available up to 2.5 metres) or use a drain hose extension kit to join an additional length to the original. Do not exceed the maximum hose length specified in the machine’s manual – overly long drain hoses reduce pump efficiency and can cause draining problems.
Do I need a plumber to install a washing machine drain hose?
Not for a straightforward connection to an existing U-bend spigot – this is a simple push-fit connection that does not require any pipe cutting or soldering. If new plumbing is needed – a standpipe installed through a wall, or a new U-bend spigot fitted where none exists – then a plumber should carry out that work. The washing machine connection itself is separate from the plumbing work.