In v6.01 of the GBXML schema the multiplicity on the Surface.AdjacentSpaceId is [1, 2]. Per the notes at the top of the 6.01 schema the multiplicity was changes in v5.12 of the schema in Aug 2014 so as to make AdjacentSpaceId a required field. Prior to that the multiplicity was [0, 2]. It is my understanding then when the number of AdjacentSpaceIds was zero that meant the surface was a shading surface. Now that a surface must have at least one AdjacentSpaceId, how is the AdjacentSpaceId for a shading surface to be specified?
Question-and-Answer Resource for the Building Energy Modeling Community
