Renovation of timber floors with structural glass: Structural and environmental performance

Abstract

A common occurrence in building renovation is the modification in the usage category that can lead to higher imposed loads, and consequently the need for structural improvements to the existing structure or to a structural element, such as timber floors. Strengthening practices oftentimes affect the originality of the building or a structural element under consideration. However, the preservation of the originality of timber floors having historical, architectural and cultural interest can be of high importance. This article provides insight into the field of timber floor strengthening techniques with regards to the requirements for conservation of the wooden built heritage. Moreover, a new strengthening technique using structural glass as a strengthening element for timber floors is presented, as reinforcing the bottom side of timber floors without compromising the appearance of the floor is an important objective of a successful intervention. In order to evaluate the performance of the newly proposed strengthening technique from a structural and environmental point of view, structural analysis and a life cycle assessment on a timber floor strengthened with cross-laminated timber panels and structural glass strips are performed. The structural analysis shows the possibility to use structural glass and still achieve a significant increase in the load-carrying capacity of the timber floor. Furthermore, the proposed strengthening technique has a lower global warming potential (GWP) and non-renewable cumulative energy demand compared to renovation and replacement with a cross-laminated timber panel, and a lower GWP compared to replacement with a reinforced concrete slab. This study not only represents the first holistic approach to evaluate the structural and environmental performance of the proposed strengthening technique, but it also addresses the aesthetically-aware design and technical limitations in the utilization of glass for the renovation of timber floors and thoroughly presents the possibilities to overcome these limitations.