This paper investigates the durability of structural glass beams that are composed of annealed glass, stainless steel reinforcement and SG (SentryGlas®) interlayer sheets. To do so, a series of pull-out tests (to investigate the shear transfer capacity of the SG) and a series of bending tests (to investigate the structural response of the beams) have been performed at different temperatures, after thermal cycling, after humidity exposure, and for long-duration loading. From the results it is concluded that the beams are highly redundant and durable, but that the effects of humidity are not yet sufficiently understood to apply them in humid environments.