Silica nanofibrous membranes are flexible, light-weight and porous materials that showcase excellent thermal and chemical resistance. However, the production via a combination of sol-gel synthesis and electrospinning depends on many factors of which the influence is not completely understood. In this work, we investigate the link between the viscosity and the electrospinnability of the tetraethylorthosilicate (TEOS) based spinning solution as a first step in linking the different scales in the process. The viscosity of the silica sol has a clear effect on the behavior of the Taylor cone and hence on the stability of the electrospinning process. Exploiting these insights is of great importance for future chemically driven tuning of silica nanofibrous membranes.