Thursday, 17 September 2026
Most landlords know about gas certificates, electrical inspections, smoke alarms and deposit protection.
Mention Legionella, however, and the response can be very different.
Some landlords believe every rental property requires an expensive annual Legionella certificate. Others assume Legionella is something that concerns hotels, hospitals and commercial buildings rather than ordinary residential property.
Neither interpretation is particularly helpful.
Landlords do have responsibilities to assess and control the risk of exposure to Legionella, but the Health and Safety Executive makes clear that ordinary domestic rental properties generally do not require routine Legionella sampling or a special annual “Legionella test certificate”.
The real issue is understanding the water system and managing foreseeable risk.
Why can an ordinary rental property develop a problem?
Legionella bacteria can develop in water systems under suitable conditions.
Risk can increase where water remains stagnant, where temperatures encourage bacterial growth or where parts of a system are rarely used.
This makes rental properties particularly interesting during periods of low occupancy.
Imagine a room in a shared property remaining empty for several weeks. The ensuite shower may not be used. Or consider an entire property sitting vacant during refurbishment.
Nothing appears to be happening.
That is precisely the problem.
Water may be remaining in parts of the system without the normal flow created by everyday occupation.
A void period changes the water conversation
Landlords often use vacant periods to decorate, clean and repair.
The water system deserves attention too.
HSE guidance specifically addresses properties left vacant and recommends considering the risks created when water is allowed to stagnate. Simple control measures can be effective in many normal domestic systems.
This is particularly relevant for landlords operating several properties.
A fully occupied house may receive constant water use without anybody consciously thinking about it. A vacant bedroom, unused bathroom or empty property behaves differently.
Good property management means recognizing when occupancy has changed the risk profile.
Does every landlord need to hire a specialist?
Not necessarily.
HSE guidance states that most landlords should be able to assess the risk in ordinary domestic hot and cold water systems themselves, provided they understand the system and the relevant risks. A specialist may be appropriate where the system is more complicated or the landlord does not feel competent to assess it.
This is important because compliance should be proportionate.
Paying somebody every year to produce a generic certificate for a straightforward property is not automatically better management.
Understanding the actual system is.
A landlord should know where water is stored, whether parts of the system are rarely used, whether temperatures are being managed appropriately and whether changes to the property have altered the risk.
The myth of the compulsory annual Legionella certificate
This deserves particular attention.
HSE states that health and safety law does not require landlords to obtain or produce a Legionella test certificate. It also says that routine testing or sampling is generally unnecessary in domestic hot and cold water systems unless particular circumstances justify it.
That does not remove the landlord's responsibility.
It changes what responsible compliance looks like.
The objective is not possession of another PDF.
The objective is identifying the risk and controlling it.
When should the assessment be revisited?
There is no universal rule requiring the assessment to be repeated every twelve months simply because a year has passed.
HSE advises reviewing it periodically and particularly where circumstances change.
A major alteration to the water system would be relevant. So could a significant change in occupancy or an extended period when part of the property has not been used.
This is another reason property records matter.
Knowing what changed, when it changed and what action followed creates a much stronger management system than simply collecting certificates because somebody once said landlords needed them.
Good compliance understands the reason behind the rule
Legionella management demonstrates a broader problem in property management.
Compliance can become a collection exercise.
Gas certificate. Electrical report. EPC. Alarm check. Another document. Another renewal date.
Documents are important, but they are evidence of management rather than the purpose of management.
The purpose is a safe home.
Sometimes that requires a formal annual inspection.
Sometimes it requires understanding why a shower that has not been used for eight weeks deserves attention before the next tenant turns it on.
*DISCLAIMER- THIS PHOTO HAS BEEN TAKEN FROM PINTEREST. *