The present paper reports the results of an investigation regarding the analysis of deflections in structural-sized beams of fast-growth Argentinean Eucalyptus grandis under a one-year loading and in indoor climate. An empirical research project with a sample containing 16 beams was carried out. 8 pieces were free of pith and another 8 pieces contained pith. The results obtained allow to compare the creep behaviour of this timber species with those reported by other researchers for both structural-sized and small-clear specimens. The research confirms the design rules adopted by Eurocode 5 for calculating the creep deflections of this timber species under a long-term load. Results also evidence a slight influence of the presence of pith on creep, confirming similar creep behaviour for different qualities of this timber species.Facultad de Ingeniería