Study of the Roof Shape of a Wooden Detached House for Minimization of LCCO₂ Emission by Genetic Algorithm

Abstract

A simulation methodology has been proposed for evaluating the performance of LCCO₂ emission of the roof shape of a Wooden Detached House (WDH) using Genetic Algorithm (GA). Annual LCCO₂ emission acting as an evaluation index was studied in this paper. The geometrical shape of a roof located in Tokyo is simulated by a Béier surface. Two types of roofs are considered in this paper: the Tiled roof shape (TRS) and the Green roof shape (GRS). Two kinds of boundary condition, which are fixed corners with free boundaries and fixed boundaries, are taken into account for both TRS and GRS. Through numerical roof shape representation evaluated by GA, we conclude that: 1) A flattened TRS is more efficient in minimizing LCCO₂ emission; 2) Dome-shaped GRS with a larger surface area and fully covered with green lawn performs the best in LCCO₂ emission minimization; 3) CO₂ absorption by green lawn has a significant effect in minimizing total LCCO₂ emission from the roof of WDH, and even LCCO₂ emission with a value below zero may occur when green lawn is laid out on a rooftop.