Seismic vulnerability of buildings is a basic component of risk that may be reduced, when necessary, by retrofitting and strengthening interventions. A procedure for assessing the vulnerability of timber roof structures has been studied and is outlined here. The procedure is organized in two levels. A first level collects data on the various elements of the structure. This information is to point out aspects of seismic interest, giving as well a detailed picture of the general state of the structure. A second step focuses on the items that mostly control seismic vulnerability. The main factors examined are the presence of unrestrained thrusts, the connection with the supporting walls, the capability of responding in both principal direction...