Exterior, Metal Roof Material, and House Building Type The house is a simple cement and steel box with elements that fold outwards to create privacy screens where needed. A perforated aluminum fence unravels from the building down toward the street. The material was selected to deter local graffiti artists from leaving their mark. Instead, a recycled brick wall serves as an appropriate canvas for street art.  Photo 1 of 7 in Angular Australian House Fits a Family’s Active Lifestyle