Vaulting Issues at Auxerre Cathedral

Harry Titus, Wake Forest University, 2006

Beginning in 2001, thanks to a generous grant from the Kress Foundation and additioanl funding from Wake Forest University, I began to work with PROGEO in Avallon on a photogrammetric survey of the Auxerre Cathedral vaults. Three-dimensional views and associated drawings were made for every high vault, every side aisle vault, and those chapel vaults that were accessible to us. The vaults range in date from ca. 1220 to ca. 1520. The initial goals were to establish vault profile norms, and ranges of deviation from those norms. Drawings in CAD format were made of each vault showing altitudes spaced at 10 centimenter intervals. In CAD, the drawings can be viewed from any side.

As a point of departure for discussion of vaulting issues, I chose the sixth north side aisle vault from the west as my "typical" vault. This vault was erected in the 1340s. (See the Chronology page on this site). I chose this vault because it is relatively square and becuase it is surrounded by arches and vaults with other distinctive characteristics. Within the range of vault types and profiles found at the cathedral, I perceive it as "typical," which is not the same as "regular." A photograph of vault 6N is below.

The voutains (vaulting compartments) are not uniform due to the differing thickness of the surrounding arches. Coursing is not composed of standarized masonry. As the masonry approaches the summits of each comparment, a series of ad-hoc adjustments in the individual pieces were made to close each of them. The vaults do not follow the curve of the arches exactly; this proves to be a common feature in vaults at Auxerre. Below is the photogrammetric drawing of this vault, as seen from above.

The contour lines are 10 centimeters apart. They indicate that the vault sections rise steeply and then level off in the last third of the vault. The summit lines of the vault rise from the boundry arches to the keystone, but not in a uniform way. The highest point of the vault lie in the eastern voutain. The vault contours are broadly regular, but each section has its own characteristics. This vault is made up of about 1000 individual stones that average 25 cms in length.

A study of all the Auxerre vaults is in the works. Stay tuned.