Legionella Risk Assessments: What Landlords Need to Know

Every UK landlord has a legal duty under the Health and Safety at Work Act 1974 to assess the risk of legionella bacteria in their rental properties. While serious outbreaks are rare in domestic settings, the legal obligation is real — and the consequences of ignoring it can be severe.

What is legionella?

Legionella is a bacteria that thrives in warm water systems (20-45°C). It can cause Legionnaires' disease — a potentially fatal form of pneumonia — when contaminated water droplets are inhaled. Showers, taps, and stored water systems are the main risk areas in domestic properties.

Your legal obligation

The HSE's Approved Code of Practice (L8) requires landlords to:

• Assess the risk of legionella exposure in all rental properties
• Implement control measures where risks are identified
• Keep records of assessments and actions taken
• Review the assessment regularly (typically every 2 years)

What a risk assessment involves

For most standard rental properties, a legionella risk assessment is straightforward. A qualified assessor will check:

• Water storage tanks (if present) — temperature, insulation, lids
• Hot water cylinder temperature (should be stored at 60°C or above)
• Showerheads and taps for limescale and biofilm
• Dead legs (sections of pipe with stagnant water)
• Any unused outlets that could harbour bacteria

A typical assessment costs £50-£150 and takes 30-60 minutes.

Practical control measures

• Set hot water cylinder thermostat to 60°C
• Ensure water reaches taps at 50°C within one minute
• Flush unused outlets weekly (advise tenants if any outlets are rarely used)
• Clean and descale showerheads quarterly
• Insulate cold water tanks and keep them below 20°C

Void periods — the hidden risk

The highest risk period is when a property stands empty. Stagnant water in pipes is ideal for bacterial growth. Before a new tenant moves in, run all taps and showers for several minutes to flush the system.

Tracking in Tendmere

Add your legionella risk assessment as a compliance item in Tendmere. Set the renewal date (typically 2 years) and you'll get automatic reminders. Upload the assessment report to the document vault for easy retrieval.