Do water-repellent sealers help control biological growths?

May 28, 2015

Benz Softwash supply softwash chemicals to the professional softwashing cleaning trade





Water repellent sealers are sometimes used on stone, brick, or render to help increase the life of the material. Brickwork and clay tiles for example, become porous after a few years, leading to the surface breaking up through the action of winter frost.

Although good for the job they are designed to do, there’s no evidence that water repellent sealers have any effect on inhibiting the return of biological growth. In fact our experience of the products we've used is that they have no effect whatever.

Note: Reducing the external porosity of a surface may lead to adverse effects on the inside of a building, in particular older buildings that were purposely designed to "breath". We suggest to never use a sealant that does not allow the surface to breath.

Sealants of this quality are not cheap but the potential damage to a building by using an inferior product could be considerably more expensive.

Our experience suggests that even the best of these sealants will benefit from a supplementary treatment of Benz Bio Cleanze. Without treatment, even if the surface is cleaned before sealing (by pressure washing for example) we’ve noticed that the surface returns to its “dirty” state surprisingly quickly. Whereas a surface treated with Bio Cleanze and then sealed should stay clean for several years.

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We hope this information is helpful.


Ben, Leo
 & Fiona

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

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

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