Practical Water Hygiene Support for Commercial Properties

Commercial buildings can contain water systems ranging from simple mains-fed office facilities to large, multi-storey systems incorporating stored water, boosted supplies, calorifiers, circulation systems and numerous tenant areas.

Changes in occupancy, refurbishment, vacant floors and alterations to tenant spaces can all affect water turnover and introduce areas of stagnation.

Source Water Compliance provides independent Legionella risk assessments and water hygiene consultancy for offices, commercial properties and multi-tenant buildings.

We work with facilities managers, property managers, landlords, managing agents and responsible persons to identify risks and provide practical recommendations for controlling them.

Request a Commercial Legionella Risk Assessment

Why Commercial Buildings Need Effective Water Management

Commercial premises can change considerably throughout their lifetime.

Floors may be refurbished, tenants may move in and out, offices can remain vacant and water systems may be altered as part of fit-out works.

This can leave parts of the original system operating differently from the way they were originally designed.

Typical systems and areas may include:

Incoming mains water supplies
Cold water storage tanks
Booster sets
Calorifiers
Hot water circulation systems
Point-of-use water heaters
Office kitchens and tea points
Staff washrooms
Showers and changing facilities
Accessible facilities
Landlord common areas
Tenant areas
Cleaning cupboards
External taps
Expansion vessels
Thermostatic mixing valves
Water softeners
Low-use outlets
Vacant floors or units
Redundant pipework

The Legionella risk assessment should consider both the physical water system and how the building is currently occupied and managed.

Commercial Legionella Risk Assessments

Our assessments involve a detailed inspection of the hot and cold water systems together with a review of existing Legionella control arrangements.

Depending on the property, this may include:

Incoming Water Supplies

Identification of incoming mains supplies and how water is distributed, stored or boosted throughout the building.

Cold Water Storage

Inspection of cold water storage tanks including condition, temperatures, configuration, turnover and associated pipework.

Hot Water Systems

Assessment of calorifiers, central hot water systems, circulation loops and point-of-use heaters.

Office and Tenant Areas

Review of representative outlets serving occupied offices, tenant spaces, kitchens, washrooms and welfare facilities.

Showers and Changing Facilities

Assessment of shower facilities, particularly where use may be intermittent or linked to cycling, gyms or staff welfare areas.

Low-Use and Vacant Areas

Identification of outlets where water turnover may be poor.

This can include:

Vacant office floors
Empty tenant units
Spare meeting rooms
Little-used kitchens
Remote washrooms
Showers with limited use
Areas awaiting refurbishment
Temporarily closed floors

Water Temperatures

Representative temperature monitoring can be undertaken to assess the effectiveness of the existing control strategy.

HSG274 Part 2 advises that, where temperature is used as the control measure, cold water should generally be maintained below 20°C where possible, while hot water should be stored at least at 60°C and reach 50°C within one minute at outlets outside healthcare environments.

System Configuration

The assessment can identify issues including:

Dead legs
Dead ends
Redundant pipework
Poor circulation
Excessive pipe runs
Heat gain into cold water systems
Stagnation
Inappropriate alterations following fit-outs

Multi-Tenant Buildings and Dutyholder Responsibilities

Commercial buildings can involve several organisations with responsibility for different parts of the water system.

For example, a landlord may be responsible for:

Incoming water → storage → central plant → landlord areas

while individual tenants may control:

Tenant kitchens → washrooms → showers → locally installed water heaters

HSG274 recognises that several dutyholders may have responsibilities within a single building.

The risk assessment should therefore establish, as far as reasonably possible:

Who controls each part of the system
Where landlord responsibility ends
Where tenant responsibility begins
Who carries out monitoring
Who manages low-use outlets
Who responds to non-compliances
Who maintains shared plant
How information is communicated between parties

Clear responsibility is particularly important in large office buildings and mixed-use developments.

Changing Occupancy and Vacant Office Space

Commercial buildings increasingly experience changing patterns of use.

Hybrid working, flexible offices and changing tenant occupancy can mean some outlets receive considerably less use than they once did.

An office floor designed for several hundred occupants may operate with substantially fewer people present on certain days.

This can affect water turnover.

Areas requiring consideration may include:

Vacant floors
Partially occupied offices
Meeting suites
Showers
Satellite kitchens
Remote washrooms
Former tenant areas
Spaces awaiting refurbishment

A suitable control programme should reflect actual use rather than assumed occupancy.

Tenant Fit-Outs and Refurbishment

Commercial properties are frequently altered as tenants move in and out.

Fit-out works can introduce new water heaters, kitchens, showers and washrooms or leave sections of older pipework redundant.

Over time this can create increasingly complicated distribution systems.

Our assessments consider evidence of:

Redundant branches
Capped pipework
Extended pipe runs
Poorly positioned water heaters
Unused outlets
Altered circulation systems
Poorly configured expansion vessels
New TMVs or flexible hoses
Incomplete decommissioning

This is particularly relevant within older buildings that have undergone multiple refurbishments.

Practical Recommendations — Not Just a Report

Our reports provide clear and prioritised recommendations based on the findings of the assessment.

Typical actions may include:

Reviewing flushing programmes
Removing redundant pipework
Improving hot water circulation
Investigating high cold water temperatures
Adjusting temperature control
Reviewing little-used outlets
Maintaining cold water storage tanks
Servicing thermostatic mixing valves
Reviewing tenant responsibilities
Improving monitoring records
Updating the Written Scheme of Control
Reviewing procedures for vacant areas
Undertaking further investigation where required

The objective is to provide proportionate recommendations that facilities and property teams can realistically manage.

Speak to a Water Hygiene Consultant

Working in Accordance With Legionella Guidance

Our commercial Legionella risk assessments take account of applicable guidance including:

HSE Approved Code of Practice L8 – Legionnaires’ disease

HSG274 Part 2 – The control of legionella bacteria in hot and cold water systems

L8 gives Approved Code of Practice status to matters including risk assessment, appointment of a competent responsible person, the control scheme and review of control measures.

HSG274 provides the detailed technical guidance used to support the assessment and control of risks within hot and cold water systems.

Supporting Commercial Properties After the Assessment

Source Water Compliance can provide ongoing support including:

Legionella Risk Assessments

Detailed assessment of hot and cold water systems throughout commercial premises.

Written Schemes of Control

Development or review of site-specific procedures detailing monitoring, responsibilities and corrective actions.

Water Hygiene Audits

Independent review of existing water hygiene arrangements and contractor performance.

Water System Schematic Drawings

Clear schematics showing principal storage, generation and distribution systems.

Water Hygiene Consultancy

Support following refurbishment, tenant changes, unusual monitoring results, sampling results or changes to the water system.

Commercial Properties We Can Support

We can provide water hygiene support for:

Office buildings
Corporate headquarters
Business centres
Co-working spaces
Multi-tenant offices
Mixed-use commercial properties
Retail properties
Shopping centres
Commercial estates
Landlord-controlled common areas
Managed office buildings
Vacant commercial properties
Property management companies
Facilities management organisations
Multi-site commercial portfolios

Independent Water Hygiene Consultancy

Source Water Compliance provides independent water hygiene consultancy focused on identifying actual risk and delivering practical recommendations.

For landlords, managing agents and facilities teams, this means providing a clear understanding of:

what the problem is, who is responsible, what needs action and what should be prioritised.

Arrange a Commercial Legionella Risk Assessment

If you manage an office, commercial property or multi-tenant building and require a Legionella risk assessment or review of your existing water hygiene arrangements, speak to Source Water Compliance.

We can discuss the property, occupancy, water systems and responsibility structure to determine the appropriate scope of assessment.