A greener, pleasanter working environment
Ecologically sound building materials help create offices with the feel-good factor
Green building is no longer a niche area. These days, sustainability does not mean compromising on aesthetics – this is where design meets ecology. For example, wood is not just a cost-effective natural building material offering good insulation and natural climatic properties, it also creates a pleasant and stylish office atmosphere.
Summary
Green building materials in Germany
A range of ecologically sound building materials are available, from mineral building materials, timber, natural insulating materials, natural paints and varnishes to natural floor coverings. The raw materials, such as clay, loam, gravel and other types of rock, can be found all over Germany, reducing the amount of transport required.
Mineral building materials
Bricks are generally made of clay and loam and used to build both exterior and interior walls. A distinction is made between backing bricks and facing bricks.
Sand lime bricks are very popular because they are relatively inexpensive and can handle high loads. They are often used for partition walls in office and commercial buildings. Lime sandstone has good heat accumulation and sound insulating properties but provides poor heat insulation. When used for exterior walls, this material is therefore usually combined with insulation cladding.
Loam products are generally used for interiors only. Loam bricks or rendering work well to control air humidity and also accumulate heat which helps create a comfortable atmosphere. Here again, the heat insulation properties are less good.
With its excellent CO2 rating, wood is one of the most environmentally friendly building materials around, particularly as – in Germany, at least – it mostly comes from forests that are sustainably managed. Timber is indispensable in roof construction. However, the amount of energy used to manufacture certain building materials out of timber, such as the processing and pressure impregnation of laminates, is relatively high.
Natural insulating materials
Insulating materials made of flax, hemp, reeds, sheep’s wool and straw bales are recommended for green buildings. Cellulose is the leading form of organic insulation in Germany. Cellulose insulation is typically made of waste paper that is ground up and mixed with borax and boric acid (fire retardants) and substances that repel insects and fungi
The most common forms of insulation used in construction are glass and rock wool, but there are ecological concerns and these materials need to be handled with care. They can pose a health hazard and recycling is not easy in loose form. Due to the heavy use of fossil fuels in its manufacture, cellular glass should only be used in damp or high pressure installations where its special merits are needed.
- Source: Bauer/Mösle/Schwarz: Green Building. Guidebook for Sustainable Architecture
Paints and varnishes
Other ecologically sound building materials include organic paints and varnishes, which are non-toxic and therefore suitable for interior use. No solvents should have been used in the manufacturing process, though. These products should also not contain isopariffins, acrylic, epoxy or polyurethane.
Flooring
When choosing flooring materials, priority should be given to environmentally friendly, healthy solutions. Linoleum is an entirely natural product made from solidified linseed oil, cork, pigments, natural resins and mineral resins and should not be confused with PVC. Wooden floors with a traditional finish and impregnated with natural resin oil are also recommended. When choosing a type of wood, always avoid non-certified tropical timber. Timber should also be free of any insecticides, pesticides and wood preservatives.
How to identify environmentally friendly building materials
When it comes to choosing ecologically sound building materials, the international ecological index (Ökoindex 3 (OI3)) is useful because it records the impact of a building material on the environment from manufacture through transportation to demolition, covering all aspects of resource and energy use. This is helpful during the planning process and facilitates good commercial and ecological decision-making.
Relevant criteria include:
- Non-renewable primary energy consumption (PEC non-renewable)
Primary energy consumption describes the amount of energy in megajoules (MJ) needed to manufacture a product. In this case, the figure relates to non-renewable primary energy. - Global warming potential (GWP)
A measure of how much a substance contributes to global warming relative to that of the same mass of carbon dioxide.
- Acidification potential (AP)
Acidification occurs when airborne pollutants are converted to acids. The pollutant binds to precipitation, reacts there and thus reduces the pH value. Acidification potential is described as the ability of a building material to build and release H+ - ions. The reference substance is sulphur dioxide.
The simplest and most effective way of achieving a low ecological index value is by taking action at the initial design and planning stage. Integrated planning – starting with the shape of the building – can minimise pollutants and emissions. Choosing sustainable materials and building quality also has a positive impact on overall costs.
