This report investigates the parameters that influence the boundary separation tables of the present New Zealand Building Code Acceptable Solutions. From an extensive literature review of theoretical and experimental research papers, revisions are proposed to some of the parameters such as emitted radiation flame projection; limiting distance and piloted ignition flux. Using these revised parameters new boundary separation tables are presented and compared to the existing tables. The new tables result in larger boundary separation (but similar separations between buildings) and potential areas for future research are suggested.