ECJ EUROPEAN Cleaning Journal

When it comes to façade maintenance and graffiti removal, different challenges apply across Europe. Ann Laffeaty finds out why this should be the case – and asks manufacturers how they tackle the various façade cleaning problems they encounter from country to country.

The protocol behind most cleaning tasks is fairly universal wherever they may be carried out. For example cleaning a kitchen, an oven or a lavatory in the UK will probably involve the same processes and similar products as would be required in France, Germany or the Czech Republic.

But façade maintenance is a different story. The challenges involved vary from country to country – and particularly so in Europe. This is due to a number of factors:  for example, different building materials are used in every nation depending on the availability of local stone, timber, clay etc.

The amount of wear a building will receive and the type soiling it is likely to attract will depend greatly on factors such as climate and humidity. And last but not least, cultural differences – such as which countries experience a significant problem with graffiti and how this issue is approached –may also have an impact.

Chairman of the board of directors for Trion Tensid Thorbjörn Bengtsson says the type of building materials used has a particular impact on the cleaning challenge. And he adds that the same stone may even have different qualities.

“For example, Chinese and Scandinavian granite could come from two different worlds,” he said. “Sandstone and limestone offer different challenges for the same reason, and clay – which is the basis for bricks - can differ in composition depending on where it is quarried.”

He says local environmental factors influence the type of soiling to be found on building frontages. “For example, the type and extent of the pollution you find will vary depending on whether the façade is in a rural location, a coastal region, an industrial area or in a city – or even in a combination of these,” said Bengtsson.

“Factors such as sun exposure, wind direction and humidity will also have an impact on the soiling, while on the micro-climate side there will even be different factors to consider when cleaning a north-facing façade compared with a south-facing one.”

According to Bengtsson every material has it challenges and the chief difficulty lies in predicting them. He adds that the height of a building will also have an effect on the difficulty of the cleaning task. “The higher the building, the more concentrated the pollution will be on the lower parts of the façade since rainwater will cause the soiling to run down the surface over time,” he said. “And the higher the building, the more difficult the planning and logistics of the cleaning operation will be.”

Tailor-made solutions

Bengtsson goes on to say that when tackling difficult façade cleaning challenges – such as when older or taller buildings are involved – the product of choice should be based on known chemistry using acids or alkalines where appropriate. “The assessment of the cleaning methodology required may have to be tailor-made,” he said. “On some occasions, blasting will be an option and this can be used if the substrate has a new surface layer after the cleaning operation.

“When it comes to maintenance, however, the most important point is to prevent water or moisture from penetrating the substrate. This is why hydrophobic treatment is often recommended following cleaning.”

Kärcher’s cleaning and hygiene technology specialist Thorsten Möwes agrees with Bengtsson that each building material presents its own challenges, and that these vary across Europe.

“Bricks and clinker are particularly difficult to clean since the fired surface needs to be maintained as a protective layer on the stones,” he said. “The surface could also be damaged when using particle-blasting, and work on these façades needs to be carried out very carefully. The bricks will have different origins and will have been produced at different firing temperatures, too, and this adds another element of uncertainty.”

High buildings need to be cleaned using professional machines, often using industrial climbers, he says. “First you have to gain access and then a long hose with water at particularly high pressures is needed to secure a sufficient working pressure on the nozzle.” He adds that regular cleaning is recommended for particularly old buildings. “The older the building, the more dirt will have accumulated on façades that have not been cleaned regularly,” he said. 

“Façades that are old and encrusted can often not be cleaned with water or high pressure since the dirt layer will be too thick. Cleaning then has to be carried out with abrasive material using the blasting method, which is both more expensive and more time-consuming.”

Like Bengtsson he says the type of soiling will vary from country to country. “A façade in an industrial area, for instance, is more likely to have a problem with greasy and oily dirt than a façade in a countryside location,” he said. “Sometimes several types of soiling can be found on one façade - this makes it difficult to formulate a cleaning regime.”

According to Möwes the drive for increased sustainability in some European countries has led to new façade cleaning challenges since it has resulted in the installation of heat insulation on façades.

“In many cases an insulating material such as polystyrene sheeting is covered with a layer of render just a few millimetres thick, or with timber cladding,” said Möwes. ”These materials must not be treated with a water jet at too high a contact pressure because that could damage the rather delicate surface.”

The increasing use of solar panels in sustainability-aware countries is another challenge says strategic business unit director of Unger Professional Worldwide Torsten Deutzmann. “Where the panels are exposed to dust, dirt or other deposits, not only do these start to look unsightly but they also affect the performance of the panels,” he says.

“Grime and soot can accumulate quickly, particularly on buildings located near roads, railway stations, farmland and on industrial parks where there is a constant stream of trucks, vans and cars,” he said.

Managing director of Graffiti Magic John Townsend says the graffiti problem also varies according to country – and adds it is difficult to keep track of where the problem is greatest. “For instance,
Poland used to be our biggest customer two years ago but last year it was Russia and this year it looks likely be Spain,” he said.

“I think it just depends on where the money is. In countries where there is no money around, graffiti is rife because no-one has the means to remove it.”

Premiere Products is another company in the anti-graffiti sector. “We find the graffiti problem tends to be much worse in Eastern Europe than elsewhere on the continent –and is particularly bad around railway stations,” said director of international sales Mark Hughes.

Thorbjörn Bengtsson agrees that the graffiti problem varies throughout Europe. “Graffiti and tagging is a fascinating phenomena,” he said. “Countries with a decent degree of welfare and a large, relatively wealthy middle class have a bigger problem with graffiti than those countries where the population has to struggle for survival. Having said that, some countries with political unrest also have a lot of graffiti based on political texts.”

So it is clear that façade cleaning challenges vary across Europe according to the age and height of the buildings; the materials of which they are made; the climate and industry of the nation concerned and the culture of its people. But there is yet another variable according to Kärcher’s Thorsten Möwes.

“One of the chief challenges across Europe is adhering to the specific cleaning requirements of the country,” he said. “For example, regulations on the use of detergent and the recycling of waste water can differ from country to country.”

And he adds that regulations can also vary when it comes to cleaning façades that are protected historical monuments.