3D-Modell -> inner or outer boundary?
If thermal zones are modelled based on the interior measurements, the inner surfaces and the air volume is modelled exactly. This is especially relevant for the detailed radiation model and comfort calculations. This entails however, a certain inaccuracy in the of the outer boundary surface as the thickness of the construction elements is not taken into account. To mitigate this, a specific gain regime for thermal bridges can be used to apply an additional loss.
If zones are modelled based on exterior measurements, the boundary surface is correct, but the zone’s reference floor area, air volume and capacitance have to be adjusted. Adapting the surface area of the construction elements is not possible.