A tree does what no building does, namely repairing the weak spots in the construction.

A tree does what no building does, namely repairing the
weak spots in the construction. This self-optimalization
process can be used in the structural engineering field.
The focus of this graduation project is to explore in what
way living tree structures can be used as load bearing
system for buildings and what the load bearing capacity
of such a structure is.
Using living trees as load bearing structures has several
potentially positive aspects. Trees repair weak spots in
the construction, they make optimal use of the strength
and durability qualities of the wood, trees have a
beneficial influence on our health, they create a balance
in the CO2 level and are the ultimate C2C load bearing
structures. Buildings in which living trees act as part of
the load bearing system can be divided into treehouses
and living tree buildings of which the last are a relative
new development. Treehouses are residences at a certain
height from ground level which are attached to a tree or
build around a tree. Living tree buildings on the other
hand are structures where the trees are an integral part
of the structure. The positive aspects of building with
living trees are used best within the living tree buildings
Trees respond to external loads and damages in the tree
by producing extra wood, called reaction wood, in order
to minimize the stresses in the structure. Trees can grow
together with other trees or non-living material when it
helps to reduce the stresses. Trees can grow together
into axial welds and cross welds or can be made into
grafts by man. Most broad-leaved trees are suitable
for living tree structures because they are able to grow
together. Needled-leaved trees contain resins which
make it difficult to grow together. When two different
types of trees are combined they prefer to have a bark
which falls off in the same direction and have the same
growth speed and size.

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