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General comment Allocation rules are used according to the ISO14044:2006. Allocation was avoided when possible and
when necessary, allocation is made based on physical shares and avoiding double calculations. Allocation was needed to evaluate the share of energy used to produce sawn timber, planed timber and glulam
timber at Kuusamo’s site.
Sawn timber and glulam production generates by-products, such as sawn dust, chips, bark and shavings.
In the model it was estimated that from 1 m3 of logs, approximately half converts to sawn timber and
remaining to by-products. From the produced sawn timber, a small production loss is estimated in the
glulam line due to planing and cutting the sawn timber in the process.
The environmental impacts have been allocated in the model to the products based on how they physically relate to them. For example, fresh chips, bark, and fresh sawdust produced in the sawing process
are not assigned heat production burdens, as they leave the process before drying process. The burden
from electricity consumption again is also allocated to the by-products because they are produced on
the same sawing line as the timber, which consumes the most electricity at the site. Physical allocation
was used because co-products have low economic value compared to the main products, contributing
less than 25 % of the total revenue.
The production of production equipment and means of transport, as well asthe machinery, equipment
and production goods needed for production and in production are excluded from the scope of the
assessment, as are the commuting of workers.
The screws required for the installation are excluded from the model, as their quantity is small. Also,
the plastic waste handling, which comes from unwrapping the timber packages at the construction
site, is excluded from the modelling as the amount of plastic waste from 1 m3 timber package is small.
The screws and the plastic represent less than 1% from the weight of the product. No other material
or energy flows have been excluded from the system boundaries.
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