Legionella is one of the landlord safety duties that is easy to overlook.
Most landlords are familiar with gas safety checks, electrical safety reports and smoke alarms. Legionella risk can feel less obvious because there is not usually a familiar annual certificate in the same way.
That does not mean landlords can ignore it.
Landlords have a responsibility to assess and control the risk of legionella in the water systems of rented properties. In many ordinary homes, the risk will be low, but it still needs to be considered.
The key message is simple: landlords should know where legionella risk may arise, take reasonable precautions and keep sensible records.
What is legionella?
Legionella is a type of bacteria that can grow in water systems.
If people breathe in tiny droplets of contaminated water, they may develop Legionnaires’ disease, a serious form of pneumonia. The risk is higher for some people, including older people, smokers, people with weakened immune systems and those with certain long-term health conditions.
Legionella is usually associated with warm, stagnant water.
That means landlords should think carefully about water systems where water can sit unused, become warm, or fail to circulate properly.
Why landlords need to think about it
Landlords are responsible for managing health and safety risks in rented property. That includes risks linked to the water system.
This does not always mean complicated testing, specialist reports or expensive certificates.
For many standard domestic properties, a simple risk assessment may be enough. But the landlord should still be able to show that the risk has been considered and that reasonable steps have been taken.
The issue is not just whether legionella is present. It is whether the landlord has managed the risk sensibly.
Where can legionella risk arise?
Legionella risk may be higher where water is stored, stagnant or kept at temperatures that allow bacteria to grow.
Possible risk areas include:
- cold water storage tanks;
- hot water cylinders;
- unused pipework;
- rarely used taps;
- showers;
- shower hoses;
- dead legs in pipework;
- water softeners;
- garden taps;
- outbuildings with water supply;
- properties left empty for long periods;
- poorly maintained water systems.
Showers are particularly relevant because they create water droplets that can be inhaled.
Empty properties and void periods
Legionella risk can increase when a property is empty.
During void periods, water may sit unused in pipes, taps and shower hoses. If the water warms up and remains stagnant, bacteria may multiply.
Landlords should pay particular attention to properties that have been:
- empty between tenancies;
- vacant during refurbishment;
- left unused while on the market;
- empty because of eviction or abandonment;
- used only occasionally.
Before a new tenant moves in, landlords should consider flushing outlets and checking that the hot and cold water systems are working properly.
What should a legionella risk assessment consider?
A legionella risk assessment does not need to be overly complicated for a simple domestic property.
It should consider:
- whether water is stored or directly supplied;
- whether cold water is kept cold;
- whether hot water reaches suitable temperatures;
- whether there are unused outlets;
- whether showers are cleaned and descaled;
- whether tanks are covered and in good condition;
- whether pipework includes dead legs;
- whether any occupants may be more vulnerable;
- whether the property has been empty;
- whether controls are already in place.
The purpose is to identify whether there is a risk and what should be done to control it.
Do landlords need water testing?
Water testing is not automatically required in every rented home.
In many ordinary domestic properties, the risk can be managed through a simple assessment and basic control measures.
Testing may be more relevant where:
- the system is complex;
- there are stored water tanks;
- there has been previous contamination;
- the property is high risk;
- tenants may be vulnerable;
- water temperatures cannot be properly controlled;
- specialist advice recommends testing.
Landlords should not assume that buying a test alone solves the issue. A test is only one part of risk management. The wider question is whether the water system is properly assessed and controlled.
Practical control measures
Landlords can often reduce risk through simple steps.
These may include:
- keeping hot water hot;
- keeping cold water cold;
- flushing outlets after void periods;
- removing redundant pipework where possible;
- cleaning and descaling shower heads;
- ensuring water tanks are covered and clean;
- checking that water flows properly from outlets;
- avoiding long periods of stagnation;
- giving tenants basic information about flushing rarely used outlets.
In many homes, these practical measures are more important than complicated paperwork.
What tenants should be told
Tenants can help reduce legionella risk, especially during normal occupation.
Landlords may wish to tell tenants to:
- regularly use taps and showers;
- report water temperature problems;
- report debris, discolouration or unusual smells;
- clean and descale shower heads where appropriate;
- flush rarely used outlets;
- tell the landlord if the property will be empty for a long period.
This information should be simple and practical.
It should not transfer the landlord’s responsibilities to the tenant, but it can help tenants understand how to reduce risk day to day.
HMOs and higher-risk properties
Legionella risk may need more detailed attention in larger or more complex properties.
This may include:
- HMOs;
- blocks of flats with shared water systems;
- properties with water tanks;
- older properties with altered plumbing;
- buildings with multiple bathrooms;
- properties with vulnerable occupiers;
- homes with outbuildings or unused outlets;
- properties with a history of water system problems.
In these cases, landlords may need a more detailed assessment or professional input.
Record-keeping matters
As with other landlord safety duties, records are important.
Landlords should keep evidence of:
- the legionella risk assessment;
- when it was carried out;
- who carried it out;
- risks identified;
- action taken;
- flushing after void periods;
- shower head cleaning or replacement;
- tank checks where relevant;
- tenant information provided;
- review dates.
For simple properties, the record may be brief. For higher-risk properties, it should be more detailed.
The important point is that the landlord can show the issue has been considered.
How often should the risk assessment be reviewed?
There is no single annual certificate system for legionella in the same way as gas safety.
However, the assessment should be reviewed when circumstances change.
A review may be sensible when:
- a new tenancy begins;
- the property has been empty;
- plumbing is altered;
- a bathroom or kitchen is refurbished;
- a water tank is added or removed;
- there are complaints about water quality;
- a tenant is known to be vulnerable;
- previous controls are no longer suitable.
Landlords should not treat a legionella assessment as something that is done once and never looked at again.
Why this matters under the Renters’ Rights Act
The Renters’ Rights Act is part of a wider move towards more formal landlord accountability.
Future reforms, including the PRS Database, Landlord Ombudsman, Awaab’s Law and stronger property standards, all point towards better records and clearer evidence that landlords are managing property risks.
Legionella may not be the most visible safety issue, but it is part of the same wider picture.
Landlords should be able to show that they have considered the health and safety risks connected with their property.
Common landlord mistakes
1. Assuming legionella only affects commercial buildings
Residential landlords also need to assess and control the risk.
2. Believing every property needs expensive testing
Testing is not always required. The first step is a proper risk assessment.
3. Ignoring void periods
Empty properties can create stagnant water risk.
4. Forgetting showers
Showers are important because they create water droplets that can be inhaled.
5. Keeping no record
Even a simple assessment should be recorded.
6. Failing to review after changes
Plumbing works, void periods and changes in occupation may require review.
7. Assuming tenants are responsible for everything
Tenants can help, but the landlord remains responsible for assessing and managing risk.
Practical checklist for landlords
Landlords should:
- assess legionella risk in each rented property;
- identify stored water, tanks and unused outlets;
- check whether hot and cold water temperatures are suitable;
- flush outlets after void periods;
- clean or replace shower heads where needed;
- remove redundant pipework where possible;
- keep tanks covered and in good condition;
- provide tenants with simple water-safety guidance;
- consider professional advice for complex systems;
- record the assessment;
- review the assessment when circumstances change;
- keep records in the property compliance file.
The key takeaway
Legionella is easy to forget because it does not come with the same familiar annual certificate as gas safety.
But landlords still need to assess and manage the risk.
For many ordinary rented homes, the assessment may be straightforward and the risk low. The important thing is that landlords consider the water system, take reasonable precautions and keep a record of what has been done.
In the modern private rented sector, hidden safety risks still matter.
Legionella is one of them.
NetRent does not provide legal advice. This article represents our understanding of rental property law at the time of writing.
Telephone: 01352 721300
Email: support@netrent.co.uk