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The genuine dry rot - Serpula lacrimans - its life-basis and other wood-destructive fungi Peter Rauch -  (Automatic translation from hs06.html)

6. Measures for the sanitation of construction-damages through it dry rot

In several federal states, also like in Saxony, an attack of the building against him/it is subject to dry rot in accordance with the construction-order (for example SächsBO § 16 Abs). 2, the duty of notification of the construction supervision-authority. The fight and damage-abolition is to be performed through a compartment-company on the basis of an expert-estimate. (Further information.)

As first meaningful fight-measure, the causes and possible moisture-sources are to be removed in principle.

If a prompt complete financial recovery cannot take place, so the growth of the fungus should be stopped most extensive. An important basis is the uncovering of the damage-area so that the wood-great commissures or other fundamental wood-parts can dry off well through with air wash round. Also direct sunlight causes a diminution of the growth-speed. As well the damage-expansion becomes visibly and can be given a talking to stoppage of the area corresponding meaningful protection-measures, as supporting, it. Without uncovering and settlement of the expansion, the affection remains a not calculable risk.

The fight-measures at an affection through the proper dry rot are in the leaflet of the scientific-technical study group for monument-care and construction-financial recovery (WTA) like follows defined:

  • Myzel including the cords and if need be fruit-bodies are to be taken away.
  • Through a treatment of chemical wood-preventatives can certainly not be reached the hyphas in the inside of the wood normally. With renewed moist-impact is not to be excluded reliably from indoors a renewed affection. Therefore, there is not any Prüfnormen for the fight of wood-destructive fungus in the wood either.
  • Attacked wood-parts including a safe distance from normally at least 1 meters above the visible affection out in longitudinal direction of the woods, to take / cut off away, is.
  • Perfoliate Schüttung including the in-thrust-boards are in sufficient safe distance over the recognizable affection out, normally 1,5 m, to take away into all directions and to replace with perfect, dry construction-materials.
    (DIN 68800 part 4, Pkt. 4 and Beuth-Kommentar to the wood-protection 1998 of the DGfH
  • In order to become not point of departure for a renewed affection, the distant fungus-materials as well as all attacked construction-materials and component parts without overdue delay are to be secured and to detoxify sorted.
  • As essential constructional measures, the causes of the elevated dampness of wood and stonework are to be determined and to remove as well as to exclude renewed dampness-impacts, especially through good insulation against ascending humidity and condensation and sufficient ventilation-circumstances.
  • If wood is installed again, they must be heeded 2 demanded constructional-constructive measures in DIN 68800 part.
  • It is to be taken care of it that component parts (wood, stonework) restored without overdue delay dries up.
  • Remained, not attacked wood as well as everything again einzubauende is wood in accordance with her/its/their endangering, to protect as prevention with an admitted wood-preventative.
  • Treatment of the stonework:
    Points of departure of the stonework-treatment are the removal of all fungus-parts (Myzel, cords, fruit-bodies), for example also the cancellation of the stonework, including the attacked finery and the 2 cm deep scraping out of the stonework-BFUs. With all fight-measures, a security-zone of 1,50 m is to be paused (into all directions) over the visibly attacked area.
    Provided cannot be abstained on chemical measures, attacked stonework is to be treated in the stonework with a broadly construction supervision-like admitted fight-means of sponge in principle in order to avoid an encroachment on neighboring woods. Come a Bohrlochtränkung or a Verpressen in question as Einbringverfahren through pressure-injection. For the treatment of stonework, Adolit M is liquid, for example, Adolit SM, Diffusit M, Diffusit MQ, impratec-MSK 10, Kulbasal M, Serpalit 2000 suitable or other means with the designation M with general construction supervision-like admission. By the DIBt, the admissions were partially confirmed no more. Is here to be heeded on the admission-number and the duration. The bonus pack to the wall-mortar can be measured exactly. It is built such a really working agent-lock. With a Mauerinjektage, however, this cannot be determined exactly, vgl. following implementation.

Dr.. Raffalski executed in Quedlinburg examinations about the Wirkstoffeinbringmenge, whose result has not been submitted to me. Here the drenched bricks were shreded and were examined. Prof. Dr.. Hoffmann, HTKW Leipzig, gave briskly at a compartment-convention with the firm to consider mixes that limits the agents brought in with the Bohrlochtränkung on few centimeters itself around the hole. To this an interesting picture from an effectiveness-examination in a little to the distribution of injection-means for this primordia of a horizontal-lock. [Raupach undWolff; construction-newspaper 5/02 S. 67-70]

Bildern zur Verteilung eines Injektionsstoffes auf Epoxydharzbasis in einem Ziegel

There will be a difference in the distribution of Injektagen on epoxyde-resin-basis or sponge-fight-means surely. (These differences should not be accepted here.) Heeding is that fluid is one-pressed only short-term with a Druckinjektage. The pores and capillaries are partially only drenched with the agent. A large part of the one-pressed fight-means spreads out in the mortar-joints. The distribution of the Myzels is macroscopic in the mortar-joint,
in stone-rips, spalling and bigger pores. Older concrete is completely perfoliate. With an intensive affection, the stonework with a gas-burner was burned down, with sponge-means flooded, and the adjacent stonework, midenstens 2 stone-situations, exchanged. At the border-work period, the mycelium still grew circa 2 cm into the new mortar with sponge-fight-means. A border between it could fungus-attack with it and the not attacked stonework is reached. However, it should be stated with it that a Grouting over borings doesn't give the security of a complete fight without hesitation. It is pointed out to it also in the Beuth-commentary to the DIN 68800 on page 82 that a fight is the purpose of destroying not inclusively possible also in the stonework. The effectiveness is based on the formation of a barrier layer. In link with it scrapes out the joint of the stonework, being burned down, and a high fight-success is achieved surely flooding with sponge-means. Expediently, attacked wall-parts should be broken off strongly. The fungus is separated from its food-source (wood and other carbon-sources) with it. In this context, "wood-preventative of new generation shall also on the contribution" is reminded. An element is measures for the protection of remaining wood-parts in the adjacent area one reorganization measures.

Through the dry rot attacked blanket-great commissureHere, a case in point of the numerous abortive financial recoveries should be shown. The left 2 to 3 blanket-great commissures (in the picture) were dry rot through it and attack something through the Ausgebreiten Hausporling (Donkioporia expansa). Also no living-affection was more available here. The brown die-break showed a halogen-containing wood-preventative, for example from Hylotox S or Hylotox I. But the blanket-great commissures inclusive Drempel-stonework beside it show a living-affection. The dampness-source (relatively small), the leaky roof was left. It will find one wood-preventatives as fight-measure, the security-areas kept not and the moisture-source doesn't remove.

A waiver of chemical measures is justifiable with:

  • In principle, fight-means are to be brought in only so much, like absolutely necessary.
  • Substitute of all woods and other materials (paper, cabbages, scatter) in the affection-area through other materials, as tabs of steel, kettle-pressure-impregnated dry wood.
  • End-lockable-ness of a crossing hands on adjacent building-parts.
  • Guarantee of the desiccation of the restored areas.

With not all of so big expansion of the fungus, the growth comes to the halt also without special fight-measures. To this, the source of the humidity must be stopped merely. At other wood-sharing, a growth could be determined with a wood-dampness of circa 12 per cent. An interpretation of 150 damages of Serpula lacrimans was tried in to perform an allocation. That is only insufficiently possible. A clear statement, when the fungus discontinues its growth, cannot be derived. For not accessible and masked areas, for example wood-great commissure-covers or behind disguises, a fight is to be performed 4 after the DIN 68800 part. For visible and constantly verifiable constructions, "milder" measures can be performed. However, it can take place from here no endangering on other component parts, and no static restrictions are available. This lasts cellar-stonework, for example, where an affection took place at a wood-shelf and the mycelium stretches also at the wall-surface. Or at freely accessible construction-woods, where only an easy affection takes place at the surface.

A waiver of chemical measures becomes respectively possible also with breaking out with the renewal of attacked parts of the stonework.

At law cases with heat, it becomes in the point 2.2. entered shortly.

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A. Biology the holzzerst.
    Fungi and insects
B. Serpula lacrimans
    (Real house-sponge)
1. Damage-picture
2. Growth factors
2.1. Humidity
2.2. Temperature
2.3. Influx light / air
2.4. Function of the mycelium
2.5. Characteristics mycelium
2.6. Cytologische processes
2.7. Spores
2.8. Environment-influxes
3. Health endangering
4. dry rot types
5. Regulation-methods
5.1. Broadly
5.2. Macroscopic
5.3. Microscopic
6. Reorganization measures
7. Damage-areas
8. remediation own-service
- Bibliographical review
- Statistics cases of damage
- Duty of notification

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Book roof-projectile
Roof-projectile-development, molds and moist brickwork

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