Espoo Museum of Modern Art
Collection Kakkonen - The Materials of the Exhibition Space
Rammed earth – gravel and unfired clay
The pedestals in this gallery were made using the ancient rammed earth technique, where gravel and clay are compacted to stone-like hardness. The surface is then polished and finished with wax.
EMMA’s pedestals are a mixture of Finnish minerals and red clay sourced locally from Vihti. Applying circular economy principles, the mixture also contains recycled surplus clay and gravel left over from other projects. The smoky shade was achieved by blending Kalanti grey granite with carbon black.
Rammed earth is fully recyclable. By dissolving the clay in water, the all-natural, chemical-free raw materials can be reused and the clay can be remoulded without generating any waste. Rammed earth is estimated to generate less than 4% of the carbon emissions of conventional concrete.
Clay is a naturally breathable material that regulates interior humidity and thermal comfort. Its porous structure softens acoustics, and its air-purifying properties have been scientifically proved to improve indoor air quality.
Rammed earth is an ancient building technique that has been practiced all around the world. The raw materials are sourced locally, directly from nature, and the simple production method involves no energy-intensive processes such as firing.
Evidence of ancient earthen structures survive from thousands of years before the Common Era. The technique grew popular in Europe in the late 18th century, when urban development and shipbuilding were causing widespread deforestation – clay thus offered a cheap, readily available alternative to timber. The rammed earth technique also spread to the Nordic region, and some surviving late 18th century earthen constructions can be found in Finland, the oldest known structure still in use today being Krouvinmäki Inn, which was built in 1784 at the Strömfors Ironworks in Ruotsinpyhtää.
The massive wooden platforms in the gallery are made from larch trees felled in winter 2022 in the Finnish Forest Research Institute’s forests in Punkaharju.
Larches are conifers of the pine family. They grow in cooler, temperate zones of the northern hemisphere, but they are not native to Finland, where larch forests are planted. Seven larch varieties grow in the Finnish Forest Research Institute’s forests, where scientists have found that Siberian and European larch grows 20% faster than native spruce. Larches thrive especially well in the rich soil and abundant sunlight of Punkaharju.
The wood used for making the platforms is estimated to be roughly 100 years old. The timber was sawn into beams in spring 2022, and then dried mechanically for several months, reducing the moisture content to about 12%. The beams were then resawn to remove any warping that occurred during drying. After resawing, the beams were milled into shape on a five-axis CNC machine, which is more precise than the human hand and eye. The wood will continue to shrink and swell in response to surrounding conditions, and cracks are liable to appear spontaneously.
The woodworking company that made the platforms will reuse the leftover timber for crafting smaller objects. The remaining scrap will be used as firewood or fuel briquettes. Zero waste was generated in the production of these platforms.