Graphic surveys tend to give and accurate geometry of vaults, but never directly reveal the way these were made. They are thus only useful as a starting point to deduce with any certainty the real designs and full-scale working drawings used by the master craftsmen of the age in their work. From this point, taking the treatises and books on stonemasonry as a reference, their original designs will be analysed and compared. In this context, the studies of the monument have brought new data to light on the design of vaulted items, which will be made known in this article. The Silk or Merchants’ Exchange, as well-known as it is studied by countless researchers, does not cease to surprise us even today. This jewel of Valencia’s civil late gothic period contains vaults which would be precursors for the models which would spread all over the Peninsula later on, in the fifteen hundreds.