Industrialization of house building implies a higher pre-fabrication level where companies have moved from the traditional on-site to the off-site assembly. Currently in Sweden there is an increasing demand for all types of households and the companies from this construction sector lack the capacity to respond to these needs. Increasing the productivity through automation is one of the ways to address this problem. Nevertheless, introducing automation solutions without the structured analysis of the production system can lead to sub-optimization. In the analysis of processes, obtaining the current state of levels of automation has proven to be a useful step towards the identification of possible automation solutions. Producers of single family timber houses often have different business strategies, therefore their processes can differ with respect to how standardized the products are. The single case study was used as a research method and has the following research question: How different are the processes and current levels of physical and cognitive automation within the off-site assembly of exterior walls in ETO and SV projects? Both assembly lines currently have rather low physical and cognitive automation levels. However, there are tasks with higher levels of physical and cognitive automation in the ETO assembly line.

Industrialization of house building has shifted the activities traditionally done at building site to the off-site assembly. The design, manufacturing processes and on-site assembly in industrialized house building are defined and documented to form a process platform, but these must be evaluated and improved to constantly develop better and more efficient practice. Lean production and philosophy are still not well understood concepts at the shop floor and wasteful activities that decrease production efficiency are often overseen. Current waste categorizations and descriptions seem not to be addressing problem areas and occurrence of waste in prefabrication of single family timber houses. The research aim is to define problem areas that occur during the prefabrication of wall modules, associate them to eight types of waste and identify key problem areas for possible development and improvement. The study was based on secondary data from five case studies that primarily focused on identifying and proposing possibilities for development of productivity. Four problem areas were identified and the future improvement efforts for the prefabrication of single family houses can be placed on developing the processes of the assembly system problem area. The possible future study can aim at quantifying these problem areas.

Purpose

The purpose of the study was to investigate the alignment between current product and manufacturing systems and how it could be achieved.

Design/Methodology/Approach

Case study research method was chosen for the collection and analysis of empirical data. The data was of qualitative nature and was collected using research techniques such as observations through video recordings of processes, documents and open and semi-structured interviews.

Findings

The variation of outer side sub-element of the exterior wall element was found to not be aligned with its corresponding assembly. A hybrid assembly of outer side sub-elements characterised by flexibility and reconfigurability can be developed.

Research Limitations/Implications

The study is limited to the exterior wall element and corresponding manufacturing system. Practical Implications The presented approach was formulated with the aim to be used both for the analysis of existing products and manufacturing systems as well as for the design of new manufacturing systems.

Originality/Value

So far, this is the first study in the context of timber house building where the alignment between product and manufacturing systems was investigated by considering product variety and flexibility of manufacturing systems.

Swedish house building companies currently face many challenges in terms of fluctuating market demand, need for flexible product offering, non-uniform governmental regulations, high costs, and long lead times. These challenges affect both internal and external efficiency of companies. Product platforms have been used for more than a decade in this industry to improve both internal and external efficiency. However, the industry is still criticized for its inefficient and costly process. Smart manufacturing has emerged as means to improve the efficiency of internal processes and the question is if and how smart manufacturing can complement and support product platforms in industrialized house building. The aim of this study is to explore the potential of smart manufacturing to complement and support product platforms in theory and practice in the context of industrialized house building. A literature review and a multiple case study were chosen to fulfill the study objective. In total fourteen semi-structured interviews were conducted in two timber house building companies. The data was analyzed within and across cases using four platform assets for categorization: components, processes, knowledge and relationships. The results show that the smart manufacturing technologies are in both theory and practice mainly supporting the process platform asset through developing vertical and horizontal IT systems integration, definition and digitalization of flexible building systems, and transferring explicit drafting and engineering knowledge into parametric modelling tools.

Vertical integration of supply chains has enabled industrialised house-building companies to develop and use product platforms. Constant changes in the external business environment, such as customer needs, legal requirements and demand fluctuations, continually compel companies to strategically align their product platforms with market position and offering accordingly. Achieving alignment is often hindered by a lack of understanding of the interplay between the external business environment, product platform, offering and market position. The knowledge on product platform alignment in this industry exists in the literature; however, a coherent description of product platform alignment is missing. The aim of this research was, therefore, to expand the knowledge on the strategic aspects of product platforms by describing product platform alignment in industrialised house building. Empirical data were collected in two Swedish companies producing timber-frame single-family houses. The developed model provides a coherent description of product platform alignment via five alignment modes that group interplays between product platform, business model and the external business environment, whereas identified challenges additionally enrich the description. Formalisation of the product platform knowledge and the changeability of manufacturing systems are identified as two main enablers of achieving product platform alignment.

There is a demand on the current markets of industrialized house building for higher product design flexibility and customization. One of the success factors in addressing this challenge efficiently is the formalization and use of product platforms through information technology applications. However, there is a lack of knowledge on how product platforms and their use should be modeled to support the development of information technology applications. The aim of this paper is therefore, to increase the knowledge on information modeling of product platforms and their use in the industrialized house building design process. The available information modeling methods were identified and analyzed using literature review while considering the contextual criteria of industrialized house building. An information modelling method for product platforms and their use in the industrialized house building design process is proposed. The information modeling rationale is synthesized using the design platform modeling and the information delivery manual modeling. The former is a PLM-oriented while the latter is a BIM-oriented information modeling method. The proposed information modeling method is composed of three parts: product platform information model, process maps and exchange requirement specification. Future work should aim for the validation of the proposed information modeling method by application on empirical data in a case study.

Industrialized house building companies producing single-family housing must efficiently respond to customer needs and contingent requirements during product specification. These are the incentives for the adoption of high-level mass customization, addressed in this research, by exploring the information modeling of product platform use. Knowledge contributions are made through a proposed information modeling method and its application in a case study. The proposed method is a synthesis between the design platform and product-oriented information delivery manual. The scope of the information delivery manual is expanded from building systems to product platforms. Moreover, the design process is considered during both product predefinition and product specification. The theoretical construct of design modules is used to describe flexible volumetric elements and thereby apply the proposed information modeling method in a case study. The research demonstrates how design modules can be modeled using design assets throughout the design process of single-family industrialized house building.