ÅTERBRUK AV TRÄ I BÄRANDE STOMMAR : Kostnads- och miljöeffektivitet i träbaserade byggstommar: En fallstudie av nyproducerat och återvunnet trä i sporthallsprojekt i Tullinge.

Purpose: This study aimed to investigate the environmental and economic differences between reusing structural timber and using newly produced timber in load-bearing construction. The focus was on glulam and cross-laminated timber (CLT), with the goal of assessing whether reused wood can be a viable and sustainable alternative in new building projects. Method: The study was based on a life cycle assessment (LCA) of a sports hall project. Manual LCA calculations were performed using national emission data, and the results were verified through the One Click LCA software. Timber quantities were obtained using Bluebeam Revu and validated in Solibri. Additionally, interviews were conducted with professionals in construction and cost management, and a literature review was used to support the analysis. Results: The LCA results showed that reused timber can significantly reduce climate impact compared to new timber, especially in early life cycle stages (modules A1–A5). However, the cost analysis revealed that reused timber is often more expensive due to high labor costs, logistical complexity, and lack of standardized processes. Interviews highlighted further challenges such as legal uncertainties, unclear responsibility, and insufficient market structures for reused materials. Conclusions: Reused timber has clear environmental advantages and is technically feasible for structural applications, but is currently not economically competitive with new timber. To make reuse more viable, improved logistics, economic incentives, and industry-wide standards are necessary. The study emphasizes that timber reuse should be considered in the early design phase to maximize its potential in sustainable construction.