How to soft wash steel cladding, eg Kingspan cladding

There is plenty of commercial work available in cleaning steel and aluminium industrial cladding, and soft washing can offer a fast and effective alternative to aggressive pressure washing.

Warehouses, factories, agricultural buildings and other commercial premises can develop green algae, black organic staining and general atmospheric dirt over time.

Because coated steel cladding is smooth and non-porous, this contamination can often be removed very effectively using a relatively mild softwash treatment.

One of the best-known manufacturers of coated steel cladding is Kingspan.

Kingspan Technical Services previously advised that Lightning Cleanze, which at that time was called Blackwash, appeared to comply with their recommendations for cleaning products.

As with any coated surface, we always recommend carrying out a small test patch first.

Watch how we soft wash steel cladding

In the short video below, Ben shows how we soft wash coated steel cladding using Lightning Cleanze, including low-pressure application from ground level and thorough rinsing afterwards.

Inspect the cladding before you start

Before applying any cleaning solution, inspect the cladding carefully.

Look for scratches, corrosion, damaged coatings and areas where bare metal has become exposed.

Older cladding may also have faded or oxidised coatings. Cleaning can remove contamination, but it cannot restore a coating that has already physically deteriorated.

Always carry out a small test patch in an inconspicuous area before treating the entire building. This allows you to check both the condition of the coating and how the surface responds to the cleaning process.

What dilution of Lightning Cleanze should you use?

For this type of smooth, factory-coated steel cladding, we normally use Lightning Cleanze at around 10:1 dilution.

That's approximately ten parts water to one part Lightning Cleanze.

Because coated cladding is smooth and non-porous, it generally does not require the stronger working solutions that may be needed when cleaning heavily contaminated porous surfaces such as render or masonry.

Applying Lightning Cleanze with the Zapplicator

For this type of work we use the Zapplicator system to dilute and apply Lightning Cleanze.

The aim is controlled, even coverage using low pressure. There is no need to blast the cladding with high pressure.

Apply enough Lightning Cleanze to wet the surface evenly while avoiding excessive run-off.

Work in manageable sections and do not allow the treatment to dry onto the cladding.

When used with a suitable pole and high-level application equipment, large areas of cladding can often be treated from ground level.

This can make high-level application much simpler and more efficient, depending on the height and design of the building and the safe working method required for the job.

Give Lightning Cleanze time to work

On smooth, non-porous cladding, the cleaning action of Lightning Cleanze can be very quick.

You will often see green algae and organic staining begin to disappear within minutes of application.

Allow the treatment sufficient contact time to work before rinsing.

If stubborn areas remain, they can be treated again or gently agitated using a suitable soft brush.

The important point is that the cleaning action is being achieved mainly by the treatment rather than by using aggressive pressure against the coating.

Rinse the cladding thoroughly

Once the contamination has been removed, rinse the entire treated area thoroughly with plenty of fresh water.

This removes the loosened organic contamination along with any remaining Lightning Cleanze and surfactant.

A water-fed pole and brush can work very well for rinsing. Suitable rinsing equipment can also be used provided the pressure reaching the cladding is kept sensible.

The objective is good water flow and thorough rinsing, not aggressive pressure washing.

Pay particular attention around joints, panel overlaps, flashings and fixings where dirty water or cleaning solution may collect.

Take care around exposed metals

Factory-coated steel cladding is not the same as exposed galvanised steel or other bare metals.

Take particular care around scratches, damaged coatings, exposed zinc, galvanised surfaces, copper, lead and other sensitive metals.

Pre-wet sensitive areas where appropriate, avoid unnecessary contact with Lightning Cleanze and rinse thoroughly with fresh water.

Also consider surrounding vegetation, vehicles, electrical equipment, air intakes and anything else close to the treatment area that may need protecting before you begin.

How to soft wash steel cladding: the basic process

The basic process is straightforward.

Inspect the cladding and carry out a test patch.

Apply Lightning Cleanze at around 10:1 using the Zapplicator and work in manageable sections using controlled, low-pressure application.

Where suitable, high-level application equipment can allow the cladding to be treated from ground level.

Give the Lightning Cleanze time to work, re-treat or gently agitate stubborn areas if required, then thoroughly rinse the entire surface with plenty of fresh water.

Done correctly, soft washing can produce a dramatic improvement to industrial steel cladding without having to rely on aggressive pressure washing.

Clean and maintain

Once the initial clean has been completed, it is worth discussing ongoing maintenance with your customer rather than allowing the cladding to become heavily contaminated again.

Organic growth often begins to return first on shaded elevations and in areas that remain damp for longer.

Periodic maintenance cleaning can therefore be considerably quicker and easier than allowing the building to deteriorate until another heavy restoration clean is required.

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

Team Benz

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