Proceedings e report - Firenze University Press

WOOD SCIENCE FOR CONSERVATION OF CULTURAL HERITAGE
structural frames on the distances 4 – 5 m, carry ridge poles, rafters, and purloins. The building is
covered with clay roof tiles. There are two types of floor structures: above the first floor mainly
massive timber floors are installed with beams adjacent one to another. Above the second floor some
of the floors are massive and some are hollow (beams on the distances ca 0.8 – 1.0 m, closed at the
bottom and the top with planks).
Fig. 2. Typical cross sections of the building [4].
3. Assessment of timber structures
Before we were involved into the project, there have been several assessments of timber structures
already performed – some of them found installed timber structures damaged in such an extent that
complete replacement has been suggested. The renovation procedure of walls and the floors in lower
storey have been proposed and performed already but the renovation of timber elements, especially of
the roof structure, has been found too complicated. Luckily, the architects wanted to preserve at least
some parts of the timber roof because it is a cultural heritage which can not be replaced and finally he
got the confirmation that this was possible.
3.1. Inspection procedure
When starting the inspection procedure, the overall impression was that the roof structures are quite in
good shape and worth to be preserved; only some structures were at first glance substantially
deformed and one major frame has already been re–strengthened due to partial failure.
Fig. 3. Typical timber roof beams and massive floors in the attics.
But after a first assessment we began with the thorough visual inspection and our impression changed.
When checking structural elements, we concentrated to the points where deterioration is expected:
supports, roof–valley elements, gutters, etc. We paid attention also to signs of biological attack
(presence of mould or wooden dust, which indicates an attack of wood fungi and insects). All findings
were documented with photos and the problematic spots were marked also on drawings. The text with
a description of findings, drawings with elaborated suggestions for replacement/strengthening of
particular elements and comprehensive photo-documentation were assembled into the final report. The
same procedure was performed also for floor structures.
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