Isopleth systems of insulation materials

Different construction materials show different susceptibilities to the growth of microorganisms. For durability and hygiene reasons it is vital to know the hygrothermal limits of the various materials at which they might be prone to mould growth in order to prevent critical installation situations. An excellent possibility to compare the resistance of different construction materials against mould infestation offers the assessment of material specific isopleth ranges. A recent investigation on different insulation materials is presented, including conventional mineral based and sustainable (plant fiber derived) types. In a practical approach the material specific isopleth systems can be used as a mould resistance indicator system similar to a "traffic light". It is possible to distinguish between a range of conditions at which mould growth is likely to occur ("red"), another range at which mould growth cannot be completely excluded ("yellow"), as well as a range at which no growth is to be expected ("green") (Sedlbauer et al., 2011). Different materials and constructions can be compared by means of this isopeth system.