Substrates
A glossary of stone and other façade materials
A regular façade cleaning regime is important for buildings of all ages. The most obvious and visible reason is aesthetic – tackling the build-up of pollutants which can obscure architectural details and diminish the overall appearance of the structure.
Most common facade materials and substrates
From a conservation perspective, an ongoing battle against the elements is essential to tackle pollutants such as exhaust and industrial fumes which, in reaction with rainwater, can become acidic and damage the façade.
Building facade materials weather and discolour at varying rates, according to a range of factors including location, ambient pollution levels, prevailing weather conditions and the substrate itself. The last of these, the stone or manmade materials from which make up the façade, also plays an important part in the suitability and efficacy of any cleaning techniques used.
At Thomann-Hanry®, we operate our own facade cleaning system called façade gommage®.
Façade gommage® projects ultra-fine dry powder onto the areas to be cleaned, dispersing them under low pressure across the surface. The powder is very but sharp and has enough mass and energy to cut through the dirt, but without affecting the stone in any way. It has a proven record of cleaning natural stone, brick, terracotta, alabaster, marble, granite, stucco, and polychrome surfaces, meeting the requirements of property managers and conservationists worldwide.
Finally, there is restoration – bringing façades back to life and uncovering deeper structural issues, such as spalling stone, which can often lie unseen and undetected beneath a layer of dirt and staining.
Our wide experience as conservation and restoration specialists encompasses a wide range of materials – and this glossary outlines the most common of these, their defining characteristics, and their response to cleaning techniques.
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