Wood is one of the
most used materials in building industry, and the progresses that have
been
made in the field of woodworking have increased its use in many
different
sectors. Glulam(glued laminated timber, also called Gluelam), for
example,
permits us to go beyond the dimensional limits of wood, to realise
trusses with
suitable section and length and to build curved beams.
Woodworking is
still very important in many fields, first of all in building industry. A
natural and ancient material (the first huts and pile-dwellings built by men
were made of wood), wood has accompanied the humankind over millennia, and
nowadays it is still able to keep pace with the times, meeting the needs
imposed by the era we are living in. One of the most urgent issues affecting
our planet and our society is pollution, but if we choose to use wood to build
houses and buildings we can help stemming, in part, this big problem. Wood is indeed
one of the most used materials in bioconstruction, as it produces a low
consumption of energy and a small amount of waste during its working. Wood has
also many other advantages: for example, it creates a unique atmosphere in each
room, building or house in which it is used, making every place very warm and
cosy. Also, wood is a resistant and cheap material as well as a good sound and
heat insulator.
Certainly wood does
not only have advantages, on the contrary, it also has some peculiarities which
might compromise its use in some fields: the size of logs, for example, i.e.
their length and section, is limited, and this might be a problem as far as
trusses building is concerned. Moreover, logs do not lend themselves naturally
to the construction of curved beams. To solve these problems many solutions
have been found over centuries, and the most recent one, and the best, is that
of producing finger jointed wood panels, which have almost unlimited fields of
applications. It was carpenter Otto Karl Friedrich Hetzer who invented, in
1901, this type of working, which makes wood very ductile, ready to be used
even in the most complicated architectural structures, and suitable for being
used without restriction in building industry and civil engineering, as well as
in art.
The production of glulam includes various steps and takes place in
appropriate plants. The first step of the process is choosing timber, which
must be as homogeneous as possible. The most used timber in Europe is spruce,
then Scots pine, larch and oak. Then logs are cut into battens, which are dried
to reach the right degree of humidity. Timber layers are then checked to verify
their humidity and defects, they are planed and glued together. Gluing is the
most important and delicate step of the whole process. At this point layers are
pressed, they are let to rest for a couple of days and are then planed to make
their surface smooth and uniform. The last steps of glulam working are
finishing and application of special products which are meant to preserve wood
from noxious agents.
