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

A simple but highly effective way to get more soft washing customers
A simple but highly effective way to get more soft washing customers

April 26, 2024

After moving to a new home people are emotionally and financially invested in the property. Why is this important for soft washing contractors?

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

View full article →

How to remove rust stains from industrial steel & aluminium cladding
How to remove rust stains from industrial steel & aluminium cladding

April 19, 2024

Industrial cladding cleans up well with Benz Lightning Cleanze but sometimes rust stains from steel fittings can detract from an otherwise excellent result.

Click the link on this page to discover the solution ...

View full article →

How to remove rust stains from render
How to remove rust stains from render

April 12, 2024

Rust stains on renders caused by flue pipes, satellite dishes, mild steel fixings, overflow pipes, etc, can be easily removed.

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

View full article →