How Do I Clean an Exterior Building Without Damaging the Render?

David Whan • Nov 09, 2020

Try our new gentle but effective soft washing exterior cleaning

Exterior of house before and after soft washing

Render is the traditional method used to protect the exterior walls of a property, and it is applied much like plastering an interior wall. Usually we will paint it whatever colour we like, but then there is not much we can do other than slowly watch it deteriorate in condition. Natural weathering of render will discolour it, and also this aging process could enable cracks to appear and moisture to penetrate the brickwork of the property. This can therefore produce considerable problems when you come to clean the exterior walls.

Weathering of render is very hard to prevent, and so too is the erosion of the render. Discolouration of the render comes from carbon staining and sometimes also the growth of algae and possibly the ingress of insect nesting. The traditional reaction to this problem with exterior walls is to jetwash them, but this use of force and this overload of water can actually cause more damage, particularly if the render is in a poor state of deterioration. Of course, more water will penetrate cracks that already exist, and segments of render can be broken off by the significant power of the water jets.

So what is the answer?

And how do you clean the exterior walls of a property if the render is in a delicate state?

Soft washing is an alternative method of cleaning the exterior walls of your property, because it is a low-pressure system that is sympathetic to its condition and will not contribute to further erosion of the wall’s surface. But it will bring out the natural colour of the surface and the chemical mix used will prevent subsequent deterioration.

How does soft washing work?

Soft washing is a low-pressure washing system which achieves more effective results because it uses a unique and specially-created chemical blend. When applied to exterior surfaces, such as walls, steps and pathways, it can have transformational effects.

The special soft wash chemical mix is applied under low pressure and is a blend of specially developed ‘soft wash’ chemicals which treat organic and non-organic staining. The chemical blend treats the exterior surface through a four-stage process:

The unique chemical mix is left on the surface of the building for a period of time depending on the nature of the structure and the type of staining or growth that is evident.
The chemical mix is rinsed off with water, also under low pressure, which should remove any organic growth that has discoloured the surface.
Any more persistent stains will then be gently steamed using a Thermotech machine.
Finally, another wash is applied which neutralises any chemical residue left from the soft washing process and applies a finishing waxing soap, to slow down any re-colonisation of organic life on the building.

Cleaning your exterior walls without jet washing

Applying this process to the exterior walls of a property is effective in creating a long-lasting clean effect, whilst also leaving exterior render in the same state it was in before. The soft washing system is ruthless in how it attacks discoloration but it is sensitive to possible structural damage to the render, and so is the perfect system for cleaning an exterior wall without damaging the render.

It’s Clean are an accredited and authorised contractor for the use of the soft washing system, and we have the skills and knowledge to advise on how and where the system should be applied. Soft washing can be effective on all exterior surfaces and is an environmentally-friendly, cost-effective and practical alternative to jet washing exterior walls, because jet washing could cause further damage without even cleaning the walls effectively.

Contact It’s Clean today and we can discuss your exterior cleaning requirements.