6 Wood Discoloration

234 8 Habitat of Wood Fungi
most important remedial treatments. Since S. lacrymans can transport water,
it cannot be excluded that sources of dampness are overlooked during repair,
and thus more-extensive measures are necessary for its control.
The first remedial treatment of dry rot infestation is described in the Bible
in Leviticus 14:33–48. Preventive measures against all house-rot fungi are
avoidance of general building defects and of those during refurbishment of old
buildings: moisture ascending in the masonry, seeping rain water, insufficient
ventilation, installation of wet or infested timber and wet fillers, allside walled
beam ends, lack of building drainage, condensation water by wrong thermal
insulation and inappropriate vapor barriers, unsatisfactory underside blockage
of buildings without cellars, wrong structure of floors, reuse of attacked
building debris, leakages in bathrooms and insufficient wood protection.
To the common causes belong also unrepaired building damage: leaky roofs,
shattered windowpanes, leaky or sweating water and heater lines, clogged or
defective rainwater and drainage facilities as well as water damage caused by
burst piping, defective washing machines and dishwasher water pipelines, cellar
floodings and fire-fighting water (Thornton 1989a; Paajanen and Viitanen
1989; Bricknell 1991; Doi 1991; Wälchli 1991).
Particularly regarding cellar fungi, flooring in new buildings should not
done too early. Damp bulk goods in ceilings shall be avoided.
The danger of infestation exists via spores and by infected timber and
wooden boxes, which are stored as firewood in damp cellars, and by mycelium
viatheshoesofworkers.
If a fungus is found, it should be first determined whether it concerns S.
lacrymans or another fungus, as this decision may require the obligation to
register the fungus and influences the extent of remedial treatments. In cases of
doubt, laboratory identification should be performed by appropriate institutes,
national testing institutions, offices for plant protection or in the laboratories of
wood preservative manufacturers. The German standard DIN 68800 demands
that if an exact species identification is not possible, then refurbishment is to
be proceeded in such a way, as if the True dry rot fungus were present.
Then the extent of the damage has to be established. German guidelines for
control measures are listed in Table 8.8 (Grosser et al. 2003).
Table 8.8. German guidelines for control measures during refurbishment
DIN 68800 Part 4: Wood preservation; control measures against wood-destroying fungi
and insects, issue 1992
Part 3: Wood preservation; protective chemical wood preservation, issue 1990
Part 2: Wood preservation in building construction; protective structural measures,
issue 1984
DIN 52175: Wood preservation; term, fundamentals, issue 1975
Concretization rule for building work (VOB part B)
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