With a glulam-based post-beam building system, a variety of building solutions is offered on the market for multi-story buildings. The building system must be adaptable to the demands of each project. However, short lead-time, efficient manufacturing and assembly must be ensured. The use of product platforms has been acknowledged as an enabler to manage external (customer) and internal (production) efficiency. The building system cannot be locked to a set of standard components as a high level of customisation is required. A set of methods and tools is needed to support the design work and to ensure that solutions stay inside the boundaries of the platform definition. The aim of this work is to map the state-of-practice in the design phase for a glulam building system from a platform theory perspective and outline a path forward for applying a sustainable platform development in companies where a component-based product platform does not suffice. Empirical data were gathered from an on-going product platform development including interviews and document analysis. The results show the lack of definition in platform-based product development from a theoretical perspective and need for development of support methods for design that align with different production strategies

The transformation from a traditional to an industrialised house building system requires a strong focus on the design phase, as several factors must be considered and the decisions taken impact both productivity and the value created for customers. The main purpose of this study is to explore the existing challenges and outline the critical success factors to be considered in the design phase of industrialised house building. A multiple-case study was conducted by linking five Swedish timber-based house building companies using different building systems. Empirical data were gathered from 27 semi-structured interviews. The findings contribute to an increased understanding of the existing challenges and knowledge on the critical success factors in the design phase by classifying them into internal and external factors. Moreover, the building system is considered a bridge linking both, and these factors can be used as a decision making support tool for the evaluation and validation of the design solution. Therefore, individual support for the prioritised factors is critical for achieving an efficient design process. The results show that fixed production, not the building system, is crucial for identifying success factors. Finally, manufacturability and assembly factors were identified as prioritised and generally important factors in industrialised building.

Industrialised house builders in Sweden have been challenged to meet the demand for housing solutions as the population has increased at a faster rate. As a result, the housing industry is currently faced with objectives to improve productivity and internal efficiency while also controlling the production cost of houses without compromising external efficiency. To remain competitive, many companies developed own building system (BS) based on fixed or partially fixed production systems with different prefabrication techniques. The challenges remain in the design phase and proper methods and tools are required to manage it. In many industries, the product platform approach has been used as a means to achieve both internal and external efficiency. However, little attention has been paid in relating the platform approach to building system support in the design phase of Industrialised house building (IHB). Thus, the main purpose of this paper is to explore the current state of the industrialised house building system and outline design support solutions for the building system from a product platform approach. Qualitative research was conducted by linking a single case company working with post and beam building system in combination with a literature review. Empirical data were gathered from five semi-structured interviews and two workshop sections. A cause-effect analysis has been conducted to realize the potential causes of challenges in the design process. The result illustrates a methodology with principle solutions that can be used as design support for the case company as a path forward and improve further from a product platform perspective.

House building projects are distinctive, and the degree of customisation creates bottlenecks in the design process and challenges for production, which results in longer lead time and higher costs. Aligned with a product platform approach, previous studies have introduced cost-effective approaches such as standardisation, modularization, configurators, etc. Still, components that cannot be completely modularized and configured due to high complexity level, may require a lot of engineering efforts during development. A platform approach that can be used to support engineer-to-order products that change over time still needs to be explored. The application of parametric modelling to automate the design process in the construction industry has the potential to further increase both the design and production efficiency. Thus, the objective of this research is to apply parametric modelling in the design of steel connectors used in a glulam based post and beam building system as part of a flexible product platform for increased design and production efficiency. A single case study has been carried out with a Swedish multi-storey house building company. Empirical data were gathered from a workshop with the design team followed by interviews, and document analysis. A computer-supported method for the steel bracket connectors has been developed, that connects post and beam components with pre-defined rules and constraints as part of the platform development. The result contributes to expanding knowledge about the development of a flexible product platform for improved design process and downstream production of customised components with parametric modelling support in the industrial post and beam buildng system.

The ability to offer customisation has been considered as a competitive advantage for industrialised house building (IHB) companies. Product platform approaches have been acknowledged as one of the prominent ways to improve both internal and external efficiency. However, the use of traditional platform-based strategies does not suffice for the design of engineer-to-order (ETO)-based components in a building system. The purpose of this research is to test and evaluate how the reuse of design assets can be achieved by using a parametric modelling approach to support the design process of ETO-based components in a post and beam building system. This is an additional study using the design platform approach (DPA) that contributes to expanding the knowledge for designing ETO-based components. This research proposes a parametric design platform method developed by following an inductive approach based on the findings from a detailed study on bracket connection with a single case study in a Swedish multi-storey house building company. The proposed method offers flexibility in modelling ETO building components, facilitates design automation, and shows a 20-times improvement in the modelling process. This approach can be used in any building system with ETO-based components by identifying, formalising, and reusing connected design assets. A key finding is that the ETO components can be shifted towards configurable solutions to achieve platform-based design.

Design for manufacturing and assembly (DfMA) has gained increased attention in the construction industry as the process has been industrialized and shifting towards a combination of factory prefabrication and assembly on site. The aim of this study is two-fold. Firstly, to apply the DfMA approach in the redesign of a steel bracket from a post and beam building system to simplify the design for reducing the cost and improving manufacturability. Secondly, to experimentally evaluate the mechanical properties of the redesigned bracket for implementation. An experimental case study has been conducted in a multistorey post and beam building system. The empirical data were collected from five semi-structured interviews and two workshops.

The result shows that the DfMA approach has the potential to improve the manufacturability and cost of building components in Industrialized house building (IHB) and is comparable to lean design. Moreover, the proposed steel bracket offers satisfactory load-bearing capacities and shows an improvement with a reduction of cost by 15%, lead time by 50%, and material efficiency by 25%. DFMA can be used as a promising approach for aligning the design phases of IHB with the production and assembly by improving cross-functional collaboration.

Industrialised house building (IHB) design incurs complexities as extensive engineering are required due to high customisation. Companies use different production strategies (PS) to develop building components ranging from standardised to customised depending on the requirements. Platform-based product development has received increased attention from IHB companies striving to be competitive in the industry. However, strategies for platform development supporting the design process are not well-defined for companies using a combination of PS in their development. This study proposes a framework using different PS in the development of a product platform to support the design phase of the post and beam IHB system. Empirical data were gathered from a Swedish multistorey house building company. The main contribution of this study is to provide insights into production strategies while designing components. Moreover, the case is used to exemplify how different subcomponents of the building system can be classified into production strategies and facilitate postponement of strategies to achieve platformbased development. The potential application of different support tools and methods in incremental platform development has been presented.