Biocide via Sodium Hypochlorite in Roof Cleaning


When you call in a professional roof cleaning company to complete some work on your home, it is important to have at least a basic comprehension of the various methods of roof cleaning so that you can make an informed decision. Whenever you are spending your hard-earned money, you should be the person making the ultimate decision, rather than the person completing the work. 

When it comes to having your roof cleaned, there are essentially three different options.

Option 1 is to power wash the roof. This, in our opinion, is a terrible idea; it could cause long term significant damage to your property and prove to be a costly decision – unless of course you have a commercial building.

The other two options are relatively similar; they essentially involve the same process but just utilize different chemicals. The purpose of this article is to try and explain the differences.

The two chemicals in question are Biocide and Sodium Hypochlorite.

Sodium Hypochlorite

One of the most popular cleaning materials used by roof cleaning companies is Sodium Hypochlorite. Sodium Hypochlorite can and does deliver excellent results almost instantly. Once the water has evaporated, all that will remain is salt, which is one of the biggest problems. It is essential upon completion of any work that this excess salt is washed away and diluted, as otherwise, if it is allowed to flood or cover plants underneath the roof, it can cause damage to both their roots and leaves. The only other negative aspect of this chemical is that your roof will look its best immediately after the work has been done, but there are no long-term benefits, and over time the moss and algae will start to return.


Biocide, which comes in many different brand name varieties, does not deliver such immediate results as sodium hypochlorite chemicals, but you will notice that the cleanliness of your roof continues to improve for about 14 days following application. The other significant advantage of using Biocide is that it will continue to clean your roof for another six months. 

It also actively prevents the regrowth of any biological organisms, such as moss, algae, mildew, and lichens, for a minimum of twelve months from the day of application. In essence, Sodium Hypochlorite delivers a short sharp shock with immediate results but no long term effect. Alternatively, the Biocide option will work slowly and steadily for at least fourteen days and then prevent any return of unsightly moss for another twelve months. Another critical difference between the two options is that Biocide cleaners are approved by the UK Government Health and Safety Executive. 

The decision about which type of cleaning products you want your contractor to use should be yours and yours alone.

In our opinion, a Biocide product delivers much better long-term results and is a better long-term investment.

If you have any further questions about having your roof cleaned, do not hesitate to contact our friendly and helpful customer service team.

Call us today on 01908 596009 for a professional roof cleaning service throughout Buckinghamshire, Northamptonshire & Hertfordshire – we at Concept Roof Cleaning have roof cleaning teams based in Milton Keynes, Luton & Bedford

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