Maakivi ehitusmaterjalina: töötlemine ja kasutus
Fieldstone has been used as a building material for many centuries. In Estonia, two large groups of stone suitable for building can be distinguished in terms of architectural outcome and construction technique: calcareous stones (mostly carbonate flagstone and dolomite) and granite boulders, or field stones. The latter cover a broad spectrum of natural igneous and metamorphic rocks (rapakivi granite, diabases, gneiss etc.). In this article, we focus on natural stone belonging to the second group: in particular how it can be processed – split with wedges or a sledgehammer – and historical means of transporting stones. We also take a look at the ethical, aesthetic and cultural aspects of fieldstone use.
Field stones were carried to Estonia by the continental glacier. In general, it can be said that fieldstone is a hard and strong stone suitable for use as a building material, which due to its density and low porosity can be used in underground and other supporting structures. These properties mean that fieldstone’s thermal conductivity is high, which is why it is not suitable for building dwellings. It has most commonly been used to build stables, cellars, barns and, to a lesser extent, taverns and other public buildings.
Fieldstone is a material with a small ecological footprint which does not participate directly in the carbon cycle, as does timber. Fieldstone processing and transport is relatively energy-intensive, but this is compensated for by the longevity of the structures made. Visually, fieldstone is a very strong and eye-catching material. The surface of each stone is different, making each structure unique. The strong visual message and the long tradition of using fieldstone as a building material are the main factors that guarantee that there are people in Estonia who still commission fieldstone buildings and smaller items.