Natural building materials occur all over the world. People have been using them to build for thousands of years. These materials include clay, wood, stone, straw and hemp.
What past constructions were made of depended on the climate and availability of resources. Nowadays natural materials are an element of construction which respect nature and leave clean water, ground and air. Natural materials are healthy and warm and help maintain a constant humidity level. Natural materials are parts of nature, so they don’t leave behind construction waste, which means they are biodegradable and can be reused.
Clay - is a product of rock erosion, which means that it is made when rock falls apart into small pieces. For many years, rocks crumble in very high or very low temperatures and water, and wind lifts the fine rock dust, which forms thick layers of clay as it falls on the ground. Depending on its place of origin, clay has a different composition, properties and color. It is the most common building material in the world, almost a third of the world's population lives in clay houses. Typically, clay is found under a 60 cm layer of humus, the top layer of earth rich in nutrients for plants. Clay is used to make walls of houses and bricks dried in the sun or fired. It is used for plastering and to make roof tiles, ceramic tiles for finishing walls, floors, stairs and bathrooms. Clay is used in the production of utensils: jugs, pots, bowls, plates and cups.
Wood - is a popular building material obtained from cut down trees all over the world. It is one of the oldest building materials used by humans. Initially, it was used as the basic building material - for the construction of cottages and houses, farm buildings, churches, bridges, and defensive structures. Whole trunks, half-trunks, boards and even braids of thin branches were used. For millennia, walls, ceilings and roofs with rails or shingle have been built of wood. Wood was used to make furniture, household appliances, dishes and tools, as well as for heating and lighting rooms (torch*). Means of transport were built of wood: boats (originally carved in one trunk), as well as ships, carts and sleighs. For two centuries, wood was the basic material for making mining support constructions. Nowadays, wood is a construction and finishing material. It is light and durable and that’s why it’s very popular. It is used to make floors, paneling, roof trusses of buildings, gazebos, sheds, fences and pergolas, furniture and toys. It is also used as an auxiliary material: for erecting scaffolding, in mining (stamps - poles supporting corridors), railway (rail sleepers), telecommunications (poles) and in the chemical industry (including paper production).
Stone - fragments of rocks which can be found in the mountains or under water. Rocks were formed millions of years ago in various conditions, for example, from lava hardening after a volcano eruption, by being crushed and transported together with water and ice. Some rocks formed because living organisms were deposited at the bottom of the oceans. Limestone rocks formed this way; sometimes we find fossils in them: traces of shells or ammonites. Stones for construction are mined in quarries, where they are cut to the required size. The stones used in construction include: marble, granite, sandstone, limestone, basalt, syenite, dolomite, alabaster, gypsum, quartz and slate. Stones, depending on their properties, are used in the construction of large, representative buildings, residential houses, walls, roads, pavements, interior wall finishing and for the production of furniture elements.
Straw is obtained from the stalks and leaves of mature crops after threshing (mechanical separation of straw from grains), e.g. wheat, rye, barley and canola, flax, field beans, or poppy seeds. It is used as feed and bedding for livestock. It was also used as wall insulation material in buildings, and rye straw was used to cover roofs (thatch). In America in the 19th century, grain harvesters began to harvest crops and compact straw into cubes. Houses were built from straw cubes at that time. This construction technique returned decades ago, when people wanted to live in healthy, natural, warm and cheaper houses.
Hemp - a very fast-growing plant: it grows as high as 1.5 to 2.5 meters high in 4 to 6 months (compared to 30 years for wood used in construction). Hemp has many applications in industry. First of all, the lignified parts called shives are obtained from hemp stalks, which in combination with lime and water make something called hemp concrete, an excellent building material. Hemp concrete buildings are warm, energy-saving, pretty, and they don’t need plastering. Hemp is not only used to make new buildings, but is also a very good material for renovating historical buildings (reconstruction).