This paper investigates the structural response and vulnerability of Blockhaus buildings under seismic loads. Blockhaus systems are widely used in daily practice for the construction of wooden houses or commercial buildings (see for example (Rubner Haus AG SpA)). Native of forested areas, they are often built also in earthquakeprone regions. Several research projects have been carried out, in order to experimentally and/or numerically assess the seismic performance of full-scale structures and small components (Branco & Araújo (2012), Piazza et al (2013), Bedon et al (2015a), Bedon et al (2015b), Bedon et al (2015c), Grossi et al (2016)). However, the seismic characterization of this construction system requires further investigations and studies, since the current standards for timber structures (e.g. Eurocode 5 (2004) and Eurocode 8 (2004)) do not provide specific recommendations for the calculation of their q-behaviour factor. In this work, based on past research contributions (Bedon et al (2015a), (2015b), (2015c)) and full-scale experimental tests (Piazza et al (2013)), Finite-Element (FE) investigations are performed on three dimensional Blockhaus buildings subjected to seismic loads by means of FE-models implemented in the ABAQUS software package (Simulia (2012)). Parametric simulations are carried out on several building archetypes, characterized by different overall geometrical properties, inter-storey floors (up to 2 levels), number and position of openings, corner joints. Design recommendations are then provided, based on the collected FE results, for a rational estimation of the corresponding q-behaviour factor.