Quick answer
Slippery algae on commercial walkways develops when damp conditions allow biofilm to build up on paving, concrete and external surfaces. This can create serious slip hazards for visitors and staff. A professional commercial pressure washing service removes algae using specialist biocide treatments followed by controlled low-pressure rinsing, helping restore safe walking surfaces and reduce liability risks.
What to do when algae develops on commercial walkways
1) Identify areas where biofilm is likely to develop
Algae and biofilm commonly develop in areas where moisture remains on surfaces for extended periods.
Facilities and maintenance managers should regularly inspect:
- Shaded walkways near buildings
- Car parks and pedestrian access routes
- Shopping centre entrances and service yards
- Ramps, pathways and external stairways
- Areas close to drainage points or landscaping
These surfaces can quickly develop slippery organic growth, particularly during colder or wetter months.
2) Understand why algae creates slip hazards
Algae growth forms a thin biological layer known as biofilm.
This layer:
- Retains moisture on surface materials
- Reduces friction on paving or concrete
- Creates a slippery surface underfoot
When combined with rain or damp conditions, biofilm can significantly increase the risk of slip-and-fall incidents.
For facilities managers responsible for public areas, addressing algae quickly is important for maintaining safe environments.
3) Consider legal and safety responsibilities
Commercial property owners and facilities teams have legal responsibilities to maintain safe environments.
In the UK, walkway safety can fall under several regulatory considerations including:
- Health and Safety at Work Act 1974
- Occupiers’ Liability Act 1957
- Workplace safety regulations relating to slips and trips
Local authorities, retail centres, car parks and publicly accessible commercial premises must ensure that surfaces are maintained in a condition that minimises risks to the public.
Failure to address slippery surfaces can lead to accidents and potential liability claims.
4) Avoid ineffective cleaning methods
Algae contamination is often difficult to remove with basic cleaning techniques.
Methods that are commonly ineffective include:
- Light washing with water alone
- Household cleaning chemicals
- Sweeping or brushing affected areas
Without proper treatment, algae can quickly return because the underlying biofilm remains active on the surface.
5) Apply professional biocide treatment
A professional commercial pressure washing service typically begins with the application of specialist biocide solutions.
This process:
- Breaks down algae and biofilm at a biological level
- Targets spores that cause regrowth
- Penetrates porous paving materials
Biocide treatments are applied carefully to ensure the treatment reaches the contamination rather than simply washing it away.
6) Use controlled low-pressure rinsing
Once the biocide treatment has worked, the surface is cleaned using controlled pressure washing.
Professional cleaning teams often use:
- Low-pressure washing systems
- Surface cleaning attachments for paving
- Controlled rinsing techniques
This approach removes contamination effectively without damaging paving joints, stone surfaces, or surrounding landscaping.
7) Restore safe surface conditions
Professional algae removal helps restore grip and safe walking conditions on commercial surfaces.
This is particularly important in:
- Retail and shopping environments
- Public pedestrian walkways
- Commercial office entrances
- Car park walkways and access routes
Maintaining clean, algae-free surfaces supports both safety compliance and the professional appearance of commercial premises.
8) Implement preventative maintenance cleaning
Regular exterior cleaning can prevent algae build-up from becoming a major safety issue.
Facilities managers may schedule commercial pressure washing services periodically to:
- Control algae and moss growth
- Maintain safe pedestrian surfaces
- Protect paving materials from long-term contamination
- Improve the appearance of commercial properties
Preventative cleaning is often far more cost-effective than responding after an accident or claim.
Common questions
Why does algae grow on commercial walkways?
Algae develops in damp, shaded areas where moisture remains on paving or concrete surfaces. Organic debris and poor drainage can also contribute to growth.
Can algae be removed with standard pressure washing?
Standard pressure washing alone may remove visible algae but may not kill the underlying bio-film. Professional cleaning often includes biocide treatments to prevent rapid regrowth.
Are biocide treatments safe to use in public spaces?
Professional biocide treatments used in commercial pressure washing are carefully selected and applied in controlled conditions to minimise risk to people, animals and surrounding environments. Cleaning teams typically follow UK health and safety guidance and manufacturer instructions when applying treatments. Areas may be temporarily managed or cordoned while the treatment is applied and rinsed to ensure safe use in public or commercial environments.
Are slippery walkways a legal risk for commercial properties?
Yes. Property owners and managers responsible for public spaces must take reasonable steps to maintain safe walking surfaces to prevent accidents.
How often should commercial walkways be pressure washed?
Frequency depends on location, shade and foot traffic. Many commercial properties benefit from scheduled exterior cleaning to manage algae growth throughout the year.
When to call Deep Clean 24 Seven
If algae, moss or biofilm is creating slippery conditions around your commercial property, Deep Clean 24 Seven provides professional commercial pressure washing service solutions designed for facilities managers and property teams.
Our specialist cleaning teams help restore safe external surfaces across commercial environments such as car parks, pedestrian walkways, shopping areas and public access routes.
Our services can include:
- Commercial pressure washing for walkways and paving
- Algae and bio-film removal
- Cleaning of car parks and public access areas
- Exterior surface restoration for commercial premises
- Scheduled exterior cleaning programmes
For advice or to arrange a professional clean:
📞 Call our Operations Team to discuss your requirements: 0203 640 8247
📧 Email: info@24sevengroup.co.uk
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