Is it a good idea to pre-heat softwash biocides?

August 11, 2021 2 Comments

Benz Lightning Cleanze for soft washing black lichen on a concrete slab patio and paths

A customer who was used to using steam and hot water cleaning systems, asked us, "Can you heat your biocides  – Bio Cleanze, Lightning Cleanze and Perma Cleanze – to around 60 degrees, or will this deteriorate the chemical?"


We replied: We don't use hot water delivery systems because we've found them to be unnecessary when our soft washing products are applied according to the instructions and in temperatures above 8 degrees.

Our experience is that the time and expense involved in pre-heating is generally not worth it because our products do an excellent job without. (The header photo attests to this, a very challenging job where we removed heavy black lichen that had been allowed to grow into the patio for several years)

In exceptionally cold conditions pre-heating may be useful, but then only to around 20 degrees (room temperature).

We suggest not warming biocides above 20 degrees because their chemical structure will start to degrade. The chemical changes would impact on our application data (dilution rates for example) which would then need to be re-evaluated.

Also, chemicals generally become more reactive when heated, so bear this in mind from a health and safety point of view.

Quick tip: Biocides tend to work more optimally at higher ambient temperatures. At lower temperatures, down to around 8 degrees, they still work but will take a longer to activate. So taking into account the expected ambient temperature is an important factor when pricing a new contract and planning work schedules. 


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


Ben, Leo, Fiona, Stevie & Anthony


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

2 Responses


August 13, 2021

Hi Joe – Bio Cleanze is not known to damage or discolour paintwork. In fact both this and Lightning Cleanze are used by professional decorators to prepare surfaces prior to painting.

Bio Cleanze is our recommended product of choice for treating the majority of roofs. This webpage explains:

Btw: Remember that a painted surface will no longer be porous, so Bio Cleanze will not be able to impart the long-term residual effect of helping to protect against re-colonisation. The same applies to sealers.

Joe McGrath
Joe McGrath

August 13, 2021

Hi Guys,
I have a customer ask me about treating their concrete pan tiles for moss growth. I’ve used the bio wash plenty of times and it works great and it gives me repeat work for controlling re growth,but this customer has his roof tiles re painted and I was wondering would the bio wash take off the paint colour of at least lighten it. I definitely won’t use hypochlorite that would damage the re coating. I’m apprehensive of using the roof scraper as that would leave scrape marks on the surface. The obvious to use would be bio wash, but I’ll work on your advice and I’ll pass it onto the customer.
I look forward to your reply.


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