Archaeologia Islandica - 01.01.2011, Page 39
A FIREWOOD EXPERIMENT AT EIRÍKSSTAÐIR: A STEP TOWARDS QUANTIFYING THE USE OF FIREWOOD
FOR DAILY HOUSEHOLD NEEDS IN VIKING AGE ICELAND
poor and the desired air flow was provided
indirectly and only partially through one of
the entrances. Instead of relating this issue
to the factor of a too high roof-construction
and too long distance from the fireplace to
the chimney, it is possible that the addition
of a second smoke-hole could have
reduced smoke effectively. In addition to
this, as already mentioned, the wood used
was well dried and therefore generated
minimal smoke, which might not have
been the case in the Viking Age, when
people would often have been forced to
use greener and damper wood which, apart
ffom diminishing the efficiency of the fire,
would have produced more smoke and
lowered the quality of the air.
A minor goal of the experiment was to
assess the possibility of cooking in houses
like this. In this particular situation,
flatbread was baked on a pan over the fire
and thus proving that a fire that was
sufficient for heating purposes also
sufficed for preparing food. The
conclusion drawn ffom this is that no
upgrading of the fire would be needed for
basic cooking. However, eventually
roasting a sheep or boiling a pot of water
could have called for higher flames and
more heat production. Nevertheless, what
we can claim with certainty is that the fire
for heating could have easily been used for
basic cooking at the same time without any
disturbance in the rate of wood
consumption or the interior temperature.
The experiment was closed with the
extinguishing of the fire and subsequent
measuring of time that was necessary for
the temperature to drop to a level
comparable with the outdoor temperature -
back to its “natural” value.
Discussion
In addition to the abovementioned
findings regarding the speed of
consumption of a quantity of birch
firewood, the testing of the cooking
capacity of fires in houses of this type and
the indications regarding ventilation in
structures of this type, and despite its
limitations and potential complexities
(primarily the short time-span of the
experiment and the fact that only three
persons/inhabitants were involved), the
experiment at Eiríksstaðir also produced
material for further research.
While the figure of 54.72 kg per day as
a daily average consumption may need
modifícation to allow for variations,
including the possibility of extreme
outdoor temperatures (which would affect
the indoor temperature) and more
controlled buming practices, it at least
makes it possible to calculate the possible
extent of woodland that could have been
felled for this purpose. Based on values
related to the defoliated biomass and tree
units per hectare in modem Icelandic
woodlands (Þ. H. Jónsson, Icelandic
Forest Research - unpublished data), a
house ofthis size (c. 45 m2,133 m3) would
require the clearance of an area of about
11 m2 per day and about 0.1 ha on a
seasonal (three-months summer) basis.
Whether this means that the firewood
requirements were non-sustainable and
that deforestation for this purpose was
drastic could be ascertained by combining
these fígures with the results of
experiments conducted at other times of
the year and adjusting for variations in
longhouse sizes at other Viking Age sites.
The results of this will make an important
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