Branching out: Timber adoption in multi-storey construction through the Diffusion of Innovations framework

Abstract

The Dutch construction sector is under increasing pressure to deliver high-density housing while reducing its environmental footprint. Conventional reliance on concrete and steel drives substantial embodied carbon emissions, putting climate commitments at risk. Engineered timber (CLT/GLT) offers significant advantages in terms of carbon reduction, prefabrication efficiency, and biophilic value. Yet despite its technical feasibility and growing policy support, timber adoption in multi-storey construction remains limited in the Netherlands. This gap is addressed in this research by examining how adoption decisions are shaped at the project level, and how barriers can be overcome through stakeholder motivation and alignment.
The research applies the Diffusion of Innovations (DOI) framework, adapted to the realities of project-based construction. A qualitative research design was adopted, starting with an extensive literature review to identify current barriers and enablers, and to establish the theoretical foundation. This was followed by a case study analysis that examined a full timber project and a hybrid timber project in the Dutch context. In total, fifteen semi-structured interviews were conducted with key stakeholders on both projects, providing perspectives on both strategic considerations and practical experiences.
Findings reveal that while timber's innovation attributes are important, they do not determine adoption on their own. Adoption was often slowed by perceived cost disadvantages, industry fragmentation, and a preference for familiar practices, even as enablers such as environmental performance, market distinctiveness, and prefabrication strengthen its appeal. Project dynamics proved decisive, with early specialist integration, integral design processes, and blurred stakeholder roles reducing uncertainty and making adoption more feasible, while their absence led to weakened ambitions and reversion to conventional materials. Motivated champions played a critical role in sustaining ambition against cost and risk pressures. Crucially, this research highlights the role of inter-project knowledge transfer as a condition for scaling adoption, since lessons often remain locked within projects. Building on these insights, the research adapts the Diffusion of Innovations framework to the fragmented, project-based construction sector by embedding motivation, project dynamics, iteration, and knowledge transfer into the adoption process. Practically, it offers recommendations to foster early collaboration, secure and maintain shared ambitions, position timber as both a sustainability and market advantage, and enable systemic learning across projects to accelerate diffusion.