Development of a Design-Driven Parametric Mass Timber Construction System for Modular High-Rise Urban Housing

Abstract

This paper presents the outcome of an ongoing research and development process at Lang Wilson Practice and Architecture Culture and Intelligent City on a parametric mass timber construction system for modular mid- to high-rise urban housing that started in 2006. The system was developed to systematically address the urban housing crisis in North America, and it is currently applied in two Canadian housing projects in seismic zones with 4 and 12 storeys in an evolution from previous modular housing projects by the companies. The first part of this paper explains the holistic, design-driven and parametric approach to urban housing, and how platform-based design is critical for an adaptable, sustainable and qualitative urbanization. Criteria of livability, affordability and sustainability inform the development of a customizable and modular mass timber building system, which can adapt to grid spacing and module sizes as well as to structural requirements for up to 18 floors in seismic zones. The building system is developed to meet Passive House certification and to be fully prefabricated. Constructional innovations within the system reduce the typical redundancy of doubled-up material layers of modular construction. In the second part, the authors explain how the building system is also the result of the development of a fully parametric design tool that allows not only for the optimization of building typology, home layouts or even energy consumption, but also automatically adapts the geometry of all mass timber building elements. This high level of parametrized building information density in an early stage of the design process allows for an unprecedented collaboration of designers, architects and engineers while ensuring constructability. In the last part the authors present a case study, explaining the advantages and challenges of such a collaborative effort and explain how they successfully obtained approvals to build a 12-storey mass timber housing project.