The set of weighting factors, g_{0} through
g_{n}, must be determined for each point of the model to be
considered more closely. These socalled gvalues are normalised such
that their sum is equal to one. If all the interior spaces are set at the
same temperature (T_{i} for T_{1} through T_{n}),
and T_{0} is defined as the exterior temperature (T_{e}),
then the equation above can be simplified to
T = g_{0}•T_{e} + (1 − g_{0})•T_{i }
and rewritten as
T = T_{i }
− g_{0}• ( T_{i} − T_{e} )
In this case, g_{0} represents a generalised version of
the fvalue familiar from the evaluation of surface temperatures for
onedimensional heat flow (based on Uvalues). Contrary to a
conventional fvalue, which applies to the entire interior surface
plane, the gvalue above is only valid for a specific point of a
thermal bridge.
Once gvalues have been characterised for the coldest points of
all interior surfaces, however, the temperatures resulting at these points
can be evaluated as simply as with the onedimensional method.
