This project falls within the EPSRC Engineering research area. Project's duration is anticipated to be 3.5 years, ending in Spring 2025. Buildings designed and constructed with a relatively young construction material - cross laminated timber (CLT) are increasingly popular. CLT buildings contribute to the Net Zero commitment by 2050 - reducing the carbon footprint in the building sector, offer comfortable living spaces, are built faster and more economically than using any other construction material. Current design guidelines on disproportionate collapse resistance of timber buildings adapt existing research on concrete and steel buildings without considering the inherent material properties of timber. Disproportionate collapse is a structural collapse where an initial local failure (e.g. loss of a column or a wall) causes a chain type damage disproportionate to the initial cause (e.g. collapse of structural bays). Timber is a light-weight material, its mechanical properties depend on dynamic effects and its failure mechanisms are usually brittle (non-ductile). An additional layer of complexity comprises consideration of high material variability of timber. The aim of the project is to study the collapse resistance of CLT buildings accounting for the ductility, rotational capacity and strength of the connections, membrane action of the CLT floor and mechanical properties. A validation and integration design approach will be adopted for the experimental and numerical work, aiming at establishing design guidelines on the design against disproportionate collapse of CLT buildings. Experiments ranging from connection to component and system level will adopt novel measurement techniques enabling an accurate calibration of numerical models. This PhD project is a unique research opportunity to advance timber research, inform and improve engineering guidelines and contribute to development of technical and non-technical communities about safe and sustainable use of CLT in construction. Partnerships to support this research project have been established with two industry partners and communication has started with other interested and emerging stakeholders with the aim to expand the current partnership network