Legionella Guidance for Landlords
In the UK landlords have a legal responsibility to manage the risks from legionella in their properties. In this article our water safety experts provide detailed legionella guidance for landlords and what they need to do to comply with the law, helping to sort fact from fiction.
The article starts by explaining what legionella is, and gives a brief definition of the term “landlord” with examples. It then goes on to consider a landlords legal responsibilities and what needs to be done. It highlights a number of practical steps that can be taken to control the risks from legionella, gives guidance for tenants, and lists precautions that can be put in place for empty buildings. It concludes by explaining the risk assessment process, the need for water testing, record keeping and how frequently everything needs to be reviewed.
What is Legionella?
Getting technical for a moment, legionella is a rod-shaped bacterium that occurs naturally in soil and water environments.
To date over 50 species have been identified although only 25 are linked to disease in humans, with Legionella pneumophila being the most dangerous – it’s responsible for over 90% of all cases of disease.
Legionella can cause diseases including the potentially serious Legionnaires’ disease, and the milder Pontiac fever.
At low temperatures (below 20oC) legionella can survive but it does not grow, however, at temperatures over 60oC it dies.
Given the right conditions including favourable growth temperatures and the availability of nutrients, legionella can multiply rapidly to contaminate water systems to dangerous levels.
What is Legionnaires’ disease?
Legionnaires’ disease is a type of pneumonia which is potentially fatal.
It is contracted when people inhale fine droplets of water (called an aerosol) which have become contaminated by Legionella bacteria – the disease can’t be contracted person-to-person.
Man-made water systems carrying both hot water and cold water can provide an environment for legionella to grow given the right conditions.
If the right growth conditions in terms of temperature occur, then legionella can thrive.
Other factors which could encourage its growth include the build-up of rust, scale or sludge in the water system which provides “food” for the bacteria, or areas of the water system that have low or no water flow causing stagnation.
Legionella can grow in any size of water system, so whatever type of water system you have it’s essential to manage the risks properly.
What is the definition of a landlord?
In the UK the legal definition of a landlord is anyone who rents out a property which they own.
This could be by licence or lease, for any term under seven years.
Landlords are involved in renting out a wide variety of properties for accommodation purposes.
They are not just individual property investors acting as private landlords… a landlord might be a company or organisation such as:
- Local council
- Housing association
- Housing co-operative organisation
- Hostels
- University or commercial provider of student accommodation
- Commercial property company
What are a landlords legal duties?
If you are a landlord who is renting out property – or even just renting out a room within your family home – then you are considered to be a business and must take responsibility for the health and safety of your tenants.
This means keeping the property safe and free from health hazards including legionella.
There is no legal requirement for a landlord to hold a “Legionella Test Certificate” – these are not recognised by the Health and Safety Executive.
The legislation which lays out a landlord’s responsibilities is the Health and Safety at Work Act 1974 (HSWA), specifically section 3(2).
Section 3(2) discusses the obligations of self-employed people to ensure that other people are not exposed to health and safety risks.
Under the HSWA, landlords are included in the self-employed group, and tenants are included in the group of people whose health and safety should be safeguarded.
Another important piece of safety legislation is COSHH, or the Control of Substances Hazardous to Health regulations.
COSHH sets out a legal framework for assessing and controlling the risk from a wide range of materials which could be hazardous, including biological agents like legionella.
Landlords are required to identify any risks, assess those risks, and then put into place processes which might be required to control the risks and so keep people safe.
Landlords and the requirement to control legionella in their properties
Since 2001, landlords of both residential and commercial properties have had a legal obligation to minimise legionella risks for their tenants.
Revision of the Health and Safety Executives ACOP L8 guidelines in 2013 made no change to the obligations of landlords.
These guidelines apply to any premises where water is used or stored, and where there is some risk of exposure to the Legionella bacteria.
What do landlords need to do to control legionella?
Landlords first have to appreciate that they have a responsibility to identify, quantify and then manage the potential legionella risks in their properties.
The start of this process should be a legionella risk assessment – the assessment does not have to be excessively long or in-depth but should identify and assess any legionella safety risks.

A risk assessment is the starting point for any for legionella control programme.
In most simple domestic properties, the risks from legionella will typically be low.
This is because the water in the plumbing system is used regularly and keeps flowing, so avoiding stagnation issues.
In most homes, both hot and cold water is used every day for drinking and food preparation, washing, showering, sanitation etc.
Nearly every building draws cold water directly from the mains supply without being stored in a water tank first.
Risk is also lower in homes with combination boilers (combi boilers), which don’t store hot water but heat it on demand for showers or kitchen use.
A landlord may perform a basic legionella risk assessment which shows that there are no risks, and that no further action is required.
The risk assessment should be reviewed regularly in case anything changes in the water system or at the property – we recommend that the assessment be reviewed at least every two years or sooner depending on circumstances.
Things landlords can do to control legionella
There is a range of simple control measures which will help keep the risks from legionella low in domestic settings.
The easiest and most reliable way of controlling legionella is to make sure temperature is controlled properly to keep hot water hot, and cold water cold – this will limit the chances of legionella growing.
Cold water at taps and other outlets should be below 20oC, and hot water should be kept hot, a minimum of 50 oC at all outlets, and above 60 oC at the hot water boiler.
Other possible control measures for Legionnaires’ disease include:
- Ensuring the water system is flushed through thoroughly before a property is let.
- Making sure that water tanks are insulated, clean, free from rust and debris, and have tightly fitting lids to stop debris getting into the water system.
- Ensuring that the hot water cylinder stores water at temperatures over 60°C.
- Removing any redundant pipework or pipework that could cause stagnation including dead-legs and dead-ends.
- Installing instant water heaters such as combi boilers and electric showers rather than relying on stored hot water.
Providing legionella guidance for tenants
Controlling the risks from legionella is not just the landlords responsibility, tenants have to take a bit of responsibility too… and it’s the job of the landlord to tell then what they need to know and do.
Ideally tenants should be told not to adjust the hot water settings once they’ve been set correctly, and to make sure that shower heads and other outlets are cleaned, descaled and disinfected regularly.
Tenants should also be told about the risks of water stagnation which can become a problem if they are away for a prolonged period of time, for example on holiday – this is where regular flushing becomes important.
There should also be a process for getting in touch with the landlord promptly if there are any problems which need to be resolved.
Showers are one of the main risk areas in domestic settings as they create and disperse fine water droplets, or aerosols.
If the shower is used regularly then the risk is greatly reduced, however, tenants should be told to clean and disinfect shower heads regularly.
Electric showers which are fed by cold water which is heated as required pose less of a risk than other showers.
Legionella precautions for empty buildings
If buildings are left unoccupied for extended periods, such as student accommodation over the summer months or rental voids, then extra steps may be required to make sure water is not stagnating in the system.
As a general rule, taps, showers and other outlets on both hot and cold water systems should be run at least once a week to keep the water flowing and stop it stagnating.
If landlords know in advance that a property is going to be empty for an extended period, then it’s worth thinking about a programme for flushing the system entirely, or draining it completely during the period when it is vacant – beware, draining a water system, if not done correctly, can cause damage to the system itself.
Can landlords assess the risks from legionella?
For most landlords, complying with the law isn’t difficult, and any steps they have to take tend to be straightforward and inexpensive.
Landlords may be able to carry out a legionella risk assessment themselves, and won’t need to be professionally trained or certified to do so, they just need to understand the basics.
If landlords prefer not to take on this responsibility, then they can also choose to get a competent risk assessment company in to do the checks and assessments for them.
Legionella testing and water sampling for landlords
In most residential settings, microbiological testing for Legionella bacteria won’t be necessary.
This type of water testing is not the same thing as monitoring the temperature of the water.
Although there are some companies which advertise the service, there is no legal requirement for a landlord to hold a “Legionella Test Certificate” – these are not recognised by the Health and Safety Executive.
Do landlords need to record what they do?
Only employers with five or more members of staff have a legal obligation to keep formal records of the legionella risk assessment and other control measures they take.
However, most landlords find it helpful to keep records for their own purposes – we also recommend that records are kept as it helps to spot trends, problems and also provides evidence of what you’ve done to keep the risks under control.
When should the legionella risk assessment be reviewed?
UK health and safety law does not set out a specific period after which the legionella risk assessment should be reviewed.
However, the risk assessment should be reviewed when anything in the system changes – we recommend the assessment be renewed at least every two years or sooner if things change.
If there is an issue getting access to properties to carry out inspections on the water services, the landlord might decide to combine these checks with annual gas service checks or other maintenance tasks.
Do the health and safety regulators proactively inspect domestic properties?
Currently in the UK there is no programme for proactive inspection of residential letting properties by either the Health and Safety Executive or local Councils.
Official bodies typically won’t ask landlords for proof of legionella risk assessments and monitoring and control programmes.
However this situation should be treated with caution, if a tenant develops Legionnaires’ disease, then the landlord may be liable for prosecution if they are found to be at fault.
The landlord would have to prove in court that they had done all they could to minimise risks from legionella.
Having a current risk assessment and an effective monitoring and legionella control process is the best way of doing this.
Specialist legionella risk management solutions
Water Treatment Services offer a range of legionella and water safety management solutions to support landlords, businesses and those responsible for the safety of water systems in the workplace.
Contact us today to learn how our water safety experts can help you manage your water systems, maintain regulatory compliance and so keep people safe.
With offices in London serving the South and South East England, Manchester (North West), Birmingham (Midlands), Bristol (South East England and Wales), Leeds (North and North East) and Glasgow (Scotland), supported by regional teams of specially trained technicians and engineers we can offer specialist legionella risk assessments, training, water testing and other risk management solutions throughout the UK and Internationally.
Contact us today to learn how our expert legionella safety solutions can help you.
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