How long does residual biocide protection last for?

January 13, 2021

Benz Bio Cleanze DDAC softwash biocide for professional soft washing

We've been asked about the length of time a property will stay clean after being treated with Benz Bio Cleanze or Perma Cleanze (both products have the same active ingredient: DDAC). So we wrote this Trade Tips post to explain.

Both Bio Cleanze and Perma Cleanze have the ability to offer long-term "residual biocide protection" against the recolonisation of porous surfaces.

This quality is the reason why they are the main products used in our "Clean & Maintain" softwash systems.

Quick tip: Residual protection only works on porous surfaces, not on smooth, non-porous surfaces such as roof slates or metal cladding.

How long does residual protection last?

Because of the many variables involved (material the treated surface is made of, local environment, care taken by a customer, skill of the contractor, prevailing weather, temperature, strength and quantity of product applied, etc, etc) it is not possible to give a "one size fits all" estimate of the exact time during which a given property will be protected from recolonisation.

Do we give customers a guarantee and/or a contract?

Our domestic customers tend not to ask this question as they trust us to do the best possible job for them, which we do.

We simply contact them every 6-36 months (timescale depends on the surface, e.g. patios can be 6-18 months, roofs up to 3 years or more) to offer them a repeat application of Bio Cleanze as part of our "Clean & Maintain" service.

Our customers are delighted to find that regular repeat applications usually costs much less than the original treatment.

Quick tip: Perma Cleanze is formulated for safe and legal use by the employees of property maintenance companies, in-house cleaning staff, and the general public. Most professional softwash cleaning contractors will use Bio Cleanze.

Commercial customers sometimes like a more formal agreement, so we offer them a "Clean & Maintain" contract in which we guarantee to keep their property clean for a year at a time, during which time we will return to re-treat a surface should that be necessary (which it rarely is).

With an annual contract in place, once the property has been initially cleaned using Benz Lightning Cleanze and/or Tornado Cleanze, all that is necessary is to give a yearly treatment of Bio Cleanze to give our customer a permanently clean property.

Our customers love this approach, as opposed to the more usual once-off soft wash treatment, then leaving the property to get dirty for several years before a customer cannot stand it any more and wants it cleaned again.

The principle has similarities to the regular cleaning of windows to give a customer permanently clean windows rather than allowing them to become seriously dirty before cleaning them again.

That approach creates considerably more work for a contractor – and therefore is much less profitable – and customers do not get to enjoy permanently clean windows.

Quick tip: Regular soft wash cleaning treatments are a win-win for both contractor and customer.

Our sincere good wishes for your prosperous business and a safe life,

Ben, Leo & Fiona


Click here to explore the full range of popular Benz softwash cleaning products

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

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