Due to the missing constraints it is recommended that MultiSurface elements should only be used to model non-volumetric parts of the building model as shown in Figure 11. Volumetric parts should be modeled as solids (see gml:Solid) | Due to the missing constraints it is recommended that MultiSurface elements should only be used to model non-volumetric parts of the building model as shown in Figure 11. Volumetric parts should be modeled as solids (see gml:Solid) |