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Legionella risk assessment for landlords

6-minute read

Landlord checking water system for Legionella
Conor Shilling

Conor Shilling

19 October 2023

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Making sure a property is free from hazards and safe for tenants should be a top priority for landlords.

Alongside things like electrical safety, it’s also important to check your water systems are safe. One of the ways you can do this is by completing a legionella risk assessment.

Find out why legionella can be a risk in rental properties, plus what landlords need to do to keep their tenants safe.

In the following guide, we cover:

What is legionella?

Legionella is a type of bacterium found in water, which can cause a pneumonia-type disease called Legionnaires.

Legionella is dormant at temperatures below 20°C and above 60°C. It grows at temperatures between 20°C and 45°C.

Legionnaires disease can be serious and has a range of symptoms including a fever, shortness of breath, and nausea. Anyone can catch Legionnaires, but the elderly, smokers, and those with chronic kidney or respiratory diseases are at a higher risk, according to the Health and Safety Executive (HSE).

The legionella bacteria is found naturally in freshwater, but it can contaminate water systems such as water tanks. If people breathe in air contaminated by legionella, it can lead to catching Legionnaires disease.

What are landlords’ responsibilities when it comes to legionella?

As a landlord, it’s your legal responsibility to make sure your property is free from hazards. This means it’s important to work out whether there’s a risk of legionella developing in your property and managing it accordingly.

Read our guide on how to become a landlord for more information on the health and safety rules you need to follow.

These days, the risk of legionella contamination in homes is quite low, but it’s still worth completing a legionella risk assessment before renting out your property.

It’s particularly important if you own an older property with a water tank. This type of water storage has a higher risk of legionella developing because the water stays in the same place and can stagnate.

What is a legionella risk assessment?

The purpose of a legionella risk assessment is to identify any risks of legionella developing in your water systems, plus testing to see if it’s already there. If you do find legionella in your property, you can use the risk assessment to outline the steps you need to take to remove it.

A standard legionella risk assessment will cover all water systems in your property, including checking taps and testing water.

This type of assessment can take around an hour. The level of depth you go into will depend on whether you hire a professional or do it yourself.

5 things to look for in a legionella risk assessment

When considering the risk of legionella in a rental property, it can help to think about the following points:

1. When was the water system last used?

If it hasn’t been used for a while or it isn’t used regularly, this could increase the risk of contamination.

According to the HSE, hot and cold systems should generally be used at least once a week. Flushing or draining the system may be necessary during periods when the property is empty.

2. Do you have any water tanks?

Water tanks pose more of a legionella risk, as the water has the chance to stagnate. The chances of legionella developing are reduced if the property’s water is supplied entirely by the mains.

3. How is the water temperature in the property?

If the cold water is running cold and the hot water is running hot, this should decrease the risk of contamination, as legionella thrives in warm water.

The minimum recommended temperature for hot water stored in tanks is 60 degrees celsius.

4. Do you have instantaneous water heaters?

Combi boilers and electric showers lower the risk of legionella developing as water is heated as it’s used rather than being stored.

5. Are shower heads regularly cleaned and disinfected?

This is another thing to check as there’s a higher risk of legionella developing in the water droplets or aerosols produced by shower heads.

Do I need a legionella risk assessment?

Although completing a legionella risk assessment for your property is a good idea, it’s not a legal requirement for landlords in England and Wales.

However if you’re based in Scotland, you’re legally obliged to do a legionella risk assessment. You can see more information on the Landlord Accreditation Scotland website.

It’s worth remembering that you do have a wider legal duty to make sure your property is safe for tenants to live in, which includes providing a water system that’s fit for purpose and free from harmful bacteria.

If you’re renting your property out for the first time or own a property with an old water system, it’s more important to check for legionella.

The government’s How to Let guide for properties in England also strongly recommends checking the risk of exposure to legionella.

How often should you do a legionella risk assessment?

There are no legal obligations for the risk assessment to be reviewed annually or biennially.

However, it’s generally recommended that you complete a legionella risk assessment before you rent out your property for the first time.

After that, you could check for legionella at the start of each new tenancy or roughly every few years (especially if you have an older water system).

Other times to do a new legionella risk assessment include:

  • if there’s significant changes to the water system. For example, changing your boiler
  • if your property’s empty for a long period between tenancies (this is particularly important if you have a water tank)

Who can do a legionella risk assessment?

A legionella risk assessment can be completed by a professional or you can do it yourself, provided you feel comfortable in your understanding of legionella.

If you have a fairly new water system that uses a combi boiler and is supplied by the mains, you should be able to do a risk assessment yourself with a bit of research.

On the other hand if you have an older water system that uses a water tank, it could be worth hiring a professional.

The alternative is to pay for a specialist company to send you a risk assessment and testing kit to complete yourself.

According to the HSE, in most cases the actions you need to take are “simple and straightforward”, so compliance doesn’t need to be “burdensome or costly”.

It adds that most landlords can assess the risk of legionella themselves and don’t need to be professionally trained or accredited.

How much is a legionella risk assessment?

A professional legionella risk assessment for a rental property could cost around £75 to £150. The bigger and older the property, the more the risk assessment is likely to cost.

You could do a risk assessment yourself for free, and you can also buy home testing kits from around £50.

Is there a legionella risk assessment template?

If you want to do a risk assessment yourself, it could be worthwhile to use a legionella risk assessment template.

A template can help you to make sure you’ve done all the right checks and keep your records up to date.

The risk assessment template from Rent Happily can help you to get started. There’s also detailed guidance for landlords from the HSE .

How to test for legionella

If you do your own risk assessment and you suspect there could be legionella in your property, you may want to test your water system.

You can buy a kit online and take samples of your water. These are sent to a lab for testing. If the tests identify legionella in the water, you’ll usually get some guidance on what to do next.

If there’s no legionella found, most companies will send you a certificate, which you can add to your records.

How to reduce the chances of legionella developing in your property

As a landlord there are things you can do to reduce the risk of legionella developing in your water supply, including:

  • covering any water tanks so that dirt and debris can’t get in
  • flossing the water system between tenancies and during void periods
  • replacing old or removing unused piping
  • checking the temperature of your hot water system to make sure it’s hot enough

Your tenants can also help you to reduce the risk of legionella developing in your property. Here are some of the things they can do:

  • contact you if the hot water isn’t working or isn’t hot enough
  • contact you if they find any dirt or debris in the water
  • circulate water in outlets that aren’t used frequently (such as a utility room tap or en-suite in a spare bedroom)
  • make sure shower heads are cleaned and disinfected regularly

How to get rid of legionella from your property

If tests show that legionella has developed in your water system, there are steps you can take to remove it.

The first thing you can do is increase the temperature of your water systems as legionella thrives in warm, stagnant water.

You should also clean your taps and shower heads regularly, and flush through your whole water system.

If you need to remove legionella from your property, it could be worth getting the help of a professional. There’s also some useful guidance from the HSE.

Do you have any unanswered questions about legionella risk assessments? Let us know in the comments below.

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Conor Shilling

Written by

Conor Shilling

Conor Shilling is a professional writer with over 10 years’ experience across the property, small business, and insurance sectors. A trained journalist, Conor’s previous experience includes writing for several leading online property trade publications. Conor has worked at Simply Business as a Copywriter for three years, specialising in the buy-to-let market, landlords, and small business finance.

We create this content for general information purposes and it should not be taken as advice. Always take professional advice. Read our full disclaimer

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