Frog Up or Down

I am exploring today, the correct geospatial set up of a CAD model, so that it may be exported correctly to IFC. You may wonder why, well its simple really, to accurately describe the position of any material, located within a component, in any element, in a 3D model we need to use the X,Y,Z coordinates. In the past, we have relied heavily on the use of a simple grid to locate column positions, and to describe the position of say a door in a 2D model, and to some extent this will still work in a 3D model, but to accurately describing the failure point within a cavity wall to a computer program, needs a spacial grid, that is linked to the real world. Enter the use of a global position system, In the UK we use the National Grid Ordnance Survey   G eographic   Cartesian coordinates   system, or Eastings and Northings, its position can be linked to almost any other grid method from the various Lat Long methods, to the variety of country grids operating about the gl...