Do just as you would in the USA. Contact the local authorizing agencies, and they will be happy to help you. Be prepared, though, because there is a difference in methodology. For example, zoning ordinances actually include a number of building code language.
When I worked in South Africa, I contacted a local engineering firm, which was able to cut to the chase for me. Of course, you will pay a consulting fee, but it is well worth it.
As I said earlier, things are different. My client had difficulty grasping the concept of allowing gravity to move materials. They would rather use pumps.
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Charles Graham AIA
Architect
O'Neal, Inc.
Greenville SC
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