The new exemption for Granny Flats could be both a prime opportunity and a potential minefield for prospective builders.  It sounds enticing on paper. Being able to construct a self-contained granny flat up to 70 square metres without needing a building consent - no council inspections or months of waiting, and lower costs.  With New Zealand’s chronic housing shortage, the Building Code exemption that came into play on January 15 this year seems like a major adjustment.  Building and Construction Minister Chris Penk said that the change will unlock up to 13,000 new dwellings over the coming decade, taking pressure off both councils and families.  “That means more jobs for builders, less stress for councils, money saved for homeowners, and greater choice for families and their dependents,” the Minister said.  However, the new legislation isn’t as straightforward as that.…