Architect Chris Moller meets Southland farmer Lachlan McDonald, who's building a modernist concrete home with a controversial roof in one of the most remote parts of NZ. Deer farmer and bachelor Lachlan McDonald is building a three-bedroom concrete home in the hopes to fill it with a family in the future. However, the choice of location is one of the most remote and stormy parts of the country - The Catlins. He's hired a top Auckland architect who is scratching his head at Lachlan's decision to project manage his first build himself. His choice of builder is also a good mate who specialises in constructing local milking sheds. Will this Grand Design be a perfect fusion of passions and experience or are these personalities destined to clash?