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2. The growth factors of the dry rot
2.1. The role of the humidity

The house-rottenness-fungi occurring in buildings are subdivided in two groups after its dampness-claim.

  1. Group only from the dry rot represents (15-30 per cent)
  2. Group of the wet-rottenness-fungis (30-80 per cent)
  3. Low fungi (from 80 per cent)

The real dry rot requires a higher wood-humidity of about only at start of its growth. 30 per cent until 40 per cent. As minimum, it becomes 17 to 20 per cent and boasted 90 per cent as maximum. (Mombächer et. 1988, to the comparison, the cellar-sponge prefers (Coniophora puteana, a wood-humidity of 45 until about. 70 per cent and this White pore-sponge (Poria vaporaria, 30 to 50 per cent. A high wood-humidity requires her/it Extended Hausporling (Donkioporia expansa, a white-rottenness-fungus. Its damages can assume a considerable scope. This often also simultaneously at the proper dry rot occurring some to dry fringe-areas is petty in the relationship. However the real dry rot prepares the bigger construction-damage over longer time since it damages this dryer wood. Donkioporia expansa needs moist wood and the fungus-mycelium in principle doesn't grow into this wood dries.

According to moisture-degree, certain wood-destructive fungi grow. Not be able to extend others respectively only very low for itself on that occasion. This fact is to be heeded if water pipe-damages or other firm Durchfeuchtungen are available, for example. With a short-term firm Durchfeuchtung, the growth of wet-rottenness-fungi, like the Muschelkrempling (Tapinella panuoides), rather occurs or one of the other above named wet-rottenness-fungis. It is one fast and rapid desiccation all wood here - and, to perform other touching component parts. (for example in the wood-great commissure-cover the wood, the fill and the adjacent stonework.) The Myzel can itself with it the not dry rot respectively only insufficiently develops, since the optimal dampness is only short-term available for its growth. Young Myzel perishes after the desiccation after a certain time. The phase of the dry-stiffness hangs from the size, that surely other environment-influxes and also from the trunk even from.

Dampness spaces with water vapor-satiated air are especially instrumental to the fungus-growth. If the atmospheric humidity sinks under 95 per cent, so the destruction-activity of the house-rottenness-fungi eases considerably. The atmospheric humidity stands in the context of the substrate-dampness.

All fungi generate waters with her/its/their metabolism-process. With the degradation of the cellulose, waters and carbonic-dioxide become free. They create "breath-waters" for itself such a part of the required humidity itself. One calls this Type of the rottenness dry-rottenness. With a good ventilation, this water can be carried off. The real dry rot has especially specialized and can also under the fiber-repletion (with about) circa 30 per cent of wood-humidity, grows.

Dry-rottenness at a wood boardPicture: Here a "dry-rottenness" of the board at an inner-wall. Water pipes or similar is not in the proximity. A Berlin oven was at this location earlier.

In several cases, the wood-humidity amounted 12 - 13 per cent over longer time. From a certain size, the Myzel can itself also on dry wood or extends other cellulose-containing materials. Here, the necessary water is transported over the Cord-mycelium.
The Cord-mycelium doesn't grow through the building all over. Therefore not even from a floor to the other. The fungus remains near the attacked wood in principle which was sufficiently moist at start of the affection. With the growth, the mycelium stretches on the wood-surface, usually into the direction, where a higher wood-humidity is available. for example, water runs into the wood-great commissure-cover with a water damage. This doesn't lie precisely normally horizontally. The water runs into a direction. This area is attacked too first. The stonework lying under it also becomes soak and remains this also long wet, so grows the Myzel between wall-stones and fineries here and wins the necessary water so. The mortar-BFUs are predominant perfoliate.
I could determine longer cords only in the low Eck-areas of the floor and Wanda-conclusions. That is also typical positions where the humidity is the biggest in the space. Since the wood is attacked on an end, it is timbering-woods, blanket-great commissures and other, damaged also on the other end, for example the federation-wall-stalks, inevitably someday. From a certain size, the mycelium can also Bauwerksteile or strata perfoliate without finding a food-source in this area. Go the reduced food-source (Wood or similar), however, tends, can so no new cell-material is built. If two floors are attacked, for example, so it usually is about two individual affection-areas. A grew over from a floor to the other is over possibly increases years, which are hardly possible in the lived in status, since the door-frames or the wallcovering of wood fall previously or the federation-wall got such rips, that already reorganization measures are carried out.

Cases in point of endangered areas, where the atmospheric humidity can be very high through insufficient ventilation:

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