Mike,
99 WAYS TO SKIN A CAT.
Check first, but you may find that 'works of art' are not covered by planning law in NZ, as your laws are basically written across from the English. Withdraw your antenna proposal in writng and build the house.

Then put up a 100 ft tall plastic banana! Or a glassfiber middle finger, that WOULD be really cool!! [Linked Image]
Some guy in the UK had a huge 50 ft glassfiber shark nosediving into his roof after a run-in with his Planning Gestapo. They went right up to the House of Lords to get an injunction to get it removed and failed.
Work of Art, not in their remit!

Alan

Wood work but can't!