It is a common occurrence for Architects to be confused with the site drawings and whether to indicate X and Y as negative or not.
The confusion arises due to South Africa being one of a few countries that use a left-hand rectilinear coordinate system. I found two articles online that every person in the industry who is concerned with coordinates should read:
Here is a proposal for a change, noting advantages and disadvantages.
While Civil 3D has a South African country kit that caters for this, it is not well suited for transmittal between Civil 3D and Revit, as Revit has no such capability.
To complicate matters further, some of our clients operate in places like Vietnam, and some of their coordinate systems are not even available in Civil 3D yet.
Now the task is even harder in that the SA company must transform foreign coordinate systems using MAP 3D.
In a recent discussion with just such a client, I have concluded the UTM or WSG84 coordinate systems are good choices to base a project on. It covers the entire planet and allows international partners to collaborate without much hassle.
I must admit there is something romantic about the idea that each country and region has their own units of measures and coordinate definitions. But in the same way Napoleon spread the Metric system, I think the time has come to embrace a method of indicating position and orientation on the planet.
This should be compatible with software and interpret-able by international stakeholders without the wasting of time trying to conform or hiring a Surveyor to cast the files into their correct format.
While this is my opinion, it must be noted that a professional surveyor must be consulted if you are to base your projects on any given coordinate system.
If you need help to combine the software in the Autodesk AEC collection to deliver your project, please contact Micrographics so we may be of assistance.