Should you scrape moss from a roof before soft washing?

March 14, 2019

Should you scrape moss from a roof before soft washing?
 

When soft washing a roof, should you first scrape moss from the roof, or not? This is a question we are frequently asked. So we thought to clarify the practicalities and legalities of removing moss from roofs in light of our experience.

A spray-only treatment – with any softwash chemical – of roof moss is never completely satisfactory and the practice contravenes the PPP (Plant Protection Products) regulations 2015 regarding the chemical treatment of moss.

Through numerous trial and error experiments over several years, manual scraping prior to treating the biofilm with Benz Bio Cleanze proved to be the most effective approach.

Spraying with Benz Lightning Cleanze

In the past we experimented with spraying moss with highly concentrated Lightning Cleanze.

This approach quickly turned the moss into a mush. The problem was that, if not removed from the roof, rain washed the mush into gutters, downpipes and drains. Obviously this could cause serious, hard to remove blockages.

Removing the mush by hand, prior to it entering the drainage system, proved to be messy, difficult, potentially dangerous and highly unpleasant.

This approach led to the possibility of active sodium hypochlorite remaining in the mush, so stringent H&S precautions, including appropriate PPE, had to be implemented.

Quick tip: Following the changes in HSE legislation from June 2015, treating moss by the chemical spraying of biocides is no longer allowed. Now, we always remove moss by manual scraping before treating the biofilm with Bio Cleanze.

Through many years of experience, we've found it to be most effective – and also to be in accordance with HSE regulations – to remove moss from a roof prior to soft washing, by using Benz Professional Roof Moss Scrapers.


We hope this information is helpful and sincerely wish you great success in your soft washing business,

The Benz team

Click here to explore the full range of Benz softwash cleaning chemicals & equipment

Benz Softwash Bio Cleanze DDAC biocide & Benz Softwash Lightning Cleanze SH sodium hypochlorite biocide

Leave a comment

Comments will be approved before showing up. Please revisit to read our response.


Also in Benz Trade Tips

Why does Benz Bio Cleanze contain IPA? (video)
Why does Benz Bio Cleanze contain IPA? (video)

May 17, 2024 2 Comments

Why do we add IPA (Isopropyl Alcohol) to Benz Bio Cleanze?

Click the link on this page to find out ...

View full article →

Resin bound bonded driveway
How to soft wash resin bonded/bound driveways

May 10, 2024

Many resin bound or bonded driveways come with guarantees and as such it's important not to invalidate them using chemicals that would degrade them.

Click the link on this page to learn the most effective methods for treating resin bound/bonded driveways ...

View full article →

Watch the dramatic "self-cleansing" power of Bio Cleanze to clean roofs (video)
Watch the dramatic "self-cleansing" power of Bio Cleanze to clean roofs (video)

May 03, 2024

How does Benz Bio Cleanze "self-cleanse" roofs through time by harnessing the natural power of sun, rain and wind?

Click the link on this page to find out ...

View full article →