ROOF CLEANING & ALGAE TREATMENT

Dolphin Tring - Tring, Hertfordshire, HP23

Client's Challenge

Dolphin Tring required a specialist roof cleaning and algae removal service to address extensive biological growth across roof areas on a commercial property.

Over time, moss and algae had accumulated across the roof surface, negatively affecting the appearance of the building and creating increased maintenance and safety risks. If left untreated, the biological growth posed risks including:

• Restricted rainwater run-off
• Increased moisture retention against roof surfaces
• Accelerated surface deterioration
• Slippery conditions during inspections and maintenance
• Ongoing regrowth without specialist treatment

The client required a contractor experienced in high-level roof cleaning, capable of working safely at height and delivering a treatment-led solution focused on long-term biological control rather than a short-term cosmetic clean.

Assessment & Planning  

APT ICC completed a roof-level assessment prior to mobilisation to determine the safest and most effective approach.

The assessment focused on:

• Extent and density of moss and algae growth
• Roof surface condition and suitability for treatment-based cleaning
• Access constraints and rope access requirements
• Safe handling and controlled application of external cleaning treatments

A tailored plan was developed to ensure physical moss removal was supported by chemical treatment, reducing the likelihood of rapid regrowth and improving long-term roof condition.

    Methodology

    The roof cleaning works were delivered using a structured, treatment-led approach:

    1. Roof inspection and work-zone preparation
    Roof areas were inspected and prepared to establish safe working zones.

    2. Manual moss removal
    Moss was manually removed from affected roof areas to eliminate bulk organic growth.

    3. Algae treatment application
    A biocidal treatment was applied to penetrate remaining algae and spores embedded within the roof surface.

    4. Controlled cleaning
    Loosened organic contamination was removed where appropriate using controlled cleaning methods suitable for roof substrates.

    5. Final inspection
    A final inspection was completed to confirm treatment coverage and completion of works.

    Roof Moss Removal at Dolphin Tring

    Site Access & Logistics

    Roof Moss Removal at Dolphin Tring

    Equipment
    • Rope access system (IRATA working-at-height capability)
    • Roof-safe manual moss removal tools
    • Controlled chemical application equipment

    Chemicals
    • Algae Free – biocidal treatment for algae and moss control

    The Results
    • Moss removed from affected roof areas
    • Algae growth treated and neutralised
    • Reduced risk of biological regrowth
    • Improved roof safety for inspections and maintenance
    • High-level works delivered safely using rope access

    The client was satisfied with both the quality of the finish and the
    safe, professional delivery of the works at height.