# Why do the .err file and .idf/.osm files use a different origin to reference vertices?

Hi, I'm trying to troubleshoot the following error:

** Warning ** CalculateZoneVolume: The Zone="0924-CORRIDOR-TZ" is not fully enclosed. To be fully enclosed, each edge of a surface must also be an edge on one other surface.
** ~~~ ** The zone volume was calculated using the floor area times ceiling height method where the floor and ceiling are the same except for the z-coordinates.
** ~~~ ** The surface "SURFACE 1614" has an edge that is either not an edge on another surface or is an edge on three or more surfaces:
** ~~~ ** **Vertex start { 32.7536, 2.5467E-002, 35.3568}
* ~~~ * Vertex end { 33.9728, 2.1372, 35.3568}**

When I find the same surface in the .osm and .idf files the vertices are listed with the following coordinate:

****2.02565, 10.36955, 3.6576, !- X,Y,Z Vertex 1 {m}**

**2.02565, 12.80795, 3.6576, !- X,Y,Z Vertex 2 {m}**

**0, 12.80795, 3.6576, !- X,Y,Z Vertex 3 {m}**

**0, 10.36955, 3.6576; !- X,Y,Z Vertex 4 {m} ****

The discrepancy in coordinates is making troubleshooting difficult. Does anyone know which origin each coordinate system is based on?

Thanks