Building with renewable raw materials

from Wikipedia, the free encyclopedia
Wooden house with green roof , outer wall made of untreated larch wood in post construction . Thermal insulation made of blown wood shavings , interior walls made of clay plaster on reed panels (interior painting casein paint ), floors made of larch and pearwood. Heating and hot water through a ground stove and solar panels .

Renewable raw materials are used in numerous sub-areas of house construction. The most important construction material here is wood . However, there are also numerous applications for other products based on natural fibers, oils, resins or even pigments. In addition to insulating materials , these include paints, wood preservatives and floor coverings. In addition to the sustainability aspect and the energy balance, these building materials are characterized by a good indoor climate and are sometimes superior to mineral and petroleum-based materials.

history

Even the first human settlements were often built entirely from renewable raw materials. Wood in particular has always been one of the most important building materials, but other natural building materials such as clay, reed, straw, flax and hemp have also been used as building materials for thousands of years.

While stone construction has become the dominant element in Central Europe, houses in other parts of the world are still predominantly made of wood. Traditional wooden houses are still being built in Scandinavia .

In the last few years, building materials made from renewable raw materials have come back into the public eye. Reasons for this are, in addition to the ecological aspects , new product developments and process technologies that allow new designs.

Materials and Applications

A large number of different renewable raw materials are used in the construction industry today. In addition to wood , linseed oil , various natural fibers , cork , essential oils , resins and other fiber components such as cellulose , hemicellulose , and also pigments are used. Typical applications for renewable raw materials are load-bearing constructions of buildings, thermal insulation, acoustic and impact sound insulation, facade cladding, reinforcing wall paneling, roofing, building elements, stairs, floor coverings, paints or also formwork oils.

Timber construction

Wood is mainly used for load-bearing and other construction elements. Lumber is used for load-bearing parts because it has the necessary mechanical properties. Solid structural timber , a dried coniferous timber, is particularly suitable .

Glulam , consisting of dried, planed, glued individual boards, is suitable for beams and columns due to its high dimensional stability . This processing method also allows great lengths and curved shapes to be created, which allows the limits set by tree growth to be overcome.

Panel- shaped wood-based materials are suitable for load-bearing and stiffening as well as boarding elements. A distinction is made between plywood , OSB , chipboard and fiberboard .

The timber construction is drywall . A distinction is made between different types of construction such as solid wood construction, half-timbered construction, skeleton construction, frame construction and panel construction.

Insulation materials

Insulation materials made from natural materials are on par with fossil and mineral products in terms of technical and building physics requirements. Many different natural materials can be used as insulation. These include flax , hemp , wood shavings , wood fibers , cork , rye , reeds , bales of straw or meadow grass .

Due to the higher heat storage capacity compared to mineral wool, insulating materials made of wood and cellulose fibers are suitable for attic spaces and thus prevent rapid heating in summer heat. A special property of natural insulation materials is their ability to absorb and release moisture. In contrast to mineral fiber products, they can absorb 20 percent of their own weight in moisture without losing their insulating properties.

Natural insulation materials are suitable for use in new buildings, for the renovation of old buildings and in monument preservation.

Floor coverings

Various floor coverings can be made from renewable raw materials. These include:

  • Wooden floors are made from different types of wood such as spruce, pine, oak, beech or cherry and olive. Typical shapes are different types of parquet such as ship parquet, strip parquet or mosaic parquet and solid wood floorboards.
  • Linoleum is made from linseed oil, various resins and fillers such as wood and cork flour. It is very durable, robust, does not become statically charged and is biodegradable.
  • Cork is obtained from the bark of the cork oak and can be used in panel form as floor and wall coverings. In Germany, cork has only been of economic importance as a floor covering for around 10–15 years. It is characterized by very good impact sound and heat insulating properties and freedom from dust.
  • Carpets can be made from a variety of different natural fibers. The most common materials used are cotton , jute , coconut and sisal fiber . Together with carpets made from animal hair, they make up around 10 percent of all textile floor coverings in Germany.

Paints

Piercing, glazes, varnishes, oils and waxes are used to design surfaces and protect materials from corrosion, UV radiation, soiling or drying out.

Natural paints are used as emulsion paints for plaster, wallpaper and panel materials and also as facade paint. In terms of opacity, these colors hardly differ from conventional paints.

There are different wall colors such as natural resin emulsion, glue paint and casein paints. In addition, various colors based on natural pigments (such as earth colors) are available. These are often perceived as more harmonious and pleasant than synthetic colors.

Glazes are thin paint films that are used to color and protect wood or walls. Glazes based on natural resin oil are often superior to conventional synthetic resin glazes in terms of wood penetration, substrate adhesion and weathering.

Natural resin oil clear lacquers , top lacquers and oil paints are suitable for painting furniture, structural elements and wall coverings. Outside, they are mainly used for cladding and garden furniture. Paints based on natural resin have excellent creeping properties and substrate adhesion and are therefore clearly superior to conventional paints.

Surfaces can be treated and impregnated with various oils and mixtures thereof, such as linseed oil , tung oil , turpentine oil .

As wax can beeswax and vegetable carnauba wax are used.

Advantages of building materials made from renewable raw materials

Building materials made from renewable raw materials have a number of positive properties that are responsible for the increasing quantities of these materials used.

They are virtually unlimited and thus protect the finite supplies of fossil raw materials. Their production requires little energy, so they reduce the climate-damaging CO 2 emissions into the atmosphere. They store the CO 2 absorbed during growth and, even during incineration or composting, do not emit more CO 2 than was absorbed during plant growth. Extraction and transport of raw materials, manufacture and installation of building products are associated with the lowest possible environmental and health risks.

They do not release any harmful substances into the room air, but can even bind them in some cases and ensure a pleasant room climate.

Due to the dry construction and the ability of many natural building materials to absorb moisture, the risk of moisture damage and mold growth is reduced.

literature

  • Technical brochures from the Competence Center for Building with Renewable Resources:
    • Natural floors I & II.
    • Surface coatings and natural colors.
    • Constructions with building materials made from renewable raw materials.
    • Roof extension with renewable raw materials.
  • J. Müssig, R. Maartens: Insulating and building with renewable raw materials. Lecture as part of the series of events organized by the Bremer Umweltberatung , September 19, 2001
  • K. Kruse, D. Venschott: Properties and potential uses of new wood-based materials in construction. Work report of the Institute for Wood Physics and Mechanical Technology of Wood, May 2001
  • Bruckner / Schneider: Naturbaustoffe Werner Verlag, Düsseldorf 1998, ISBN 3-8041-4140-4
  • Kurt Schönburg Natural substances in buildings, properties, application ,: Editor: German Institute for Standardization eV -DIN-, Beuth Verlag, 2010, 280 pp. ISBN 978-3-410-17355-7  

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