K-Render walls can give your commercial building a professional, sophisticated appearance - but only when they are kept looking their best. They can also stand up to a variety of weather conditions and will stay the distance when properly maintained.  Part of that proper maintenance entails regular cleaning, typically once every few years under normal conditions. Cleaning a rendered exterior surface requires knowledge, experience and the right equipment and supplies.

It’s important to keep the exterior of a building clean for a variety of reasons, not all of which are purely cosmetic.  While you may think that a dingy, dark surface is simply accrued dust or dirt, it’s more often organic matter from algae, mould or moss, especially when the weather has been mild, damp or humid. These living invaders can infiltrate deep into the material covering the exterior, causing it to deteriorate faster than it should. 

But it’s not just important to clean - it’s important to clean properly.  Cleaning with equipment, chemicals, or methods that are inappropriate for use on the particular style of render used on your building can cause damage. Sometimes, this damage is immediately visible, but frequently it’s invisible to the eye. Nonetheless, it encourages more vigorous growth of moss, mildew, algae, and mould, and can significantly shorten the life of your exterior, necessitating repairs and restoration.

How are Rendered Walls Cleaned?

Pressure Washing

Most cleans are carried out using a specialist high temperature/low impact pressure washer, such as the DOFF or Thermatech systems. While this type of pressure washing is often the most efficient way of cleaning a rendered wall, it must be done with professional care.  Pressure that is too high, or improperly applied, can result in serious damage to the wall.  Special care should be used to spread the pressure across the wall evenly during application.

Hand Scrubbing

In some cases, limited amounts of manual cleaning may be necessary.  Professionals will use specialist brushes specially designed for this purpose, to remove grime without damaging the exterior of the building.  As the dirt and organic material is dislodged, it should be rinsed away with clear water to ensure that the residue doesn’t dry in place.

Cleaning Chemicals

There are a variety of cleaning supplies which can be used to clean rendered walls. The type of chemical used will depend upon the material used for the exterior as well as the nature of the dirt or growth on the walls.  Different cleaners will be used for rust versus green or red algae, for example.

A professional render cleaning service will know which chemicals and what methods to use to give your commercial building the most attractive, long-lasting results.


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