structural:scholar_edition, structural:expansion
Elevations and the search for height

Gothic architecture was a continual search for greater height, thinner walls, and more light. This was clearly illustrated in the evolving elevations of the cathedrals.

In Early Gothic architecture, following the model of the Romanesque churches, the buildings had thick, solid walls with a minimum of windows in order to give enough support for the vaulted roofs. An elevation typically had four levels. On the ground floor was an arcade with massive piers alternating with thinner columns, which supported the six-part rib vaults. Above that was a gallery, called the tribune, which provided stability to the walls, and was sometimes used to provide seating for the nuns. Above that was a narrower gallery, called the triforium, which also helped provide additional thickness and support. At the top, just beneath the vaults, was the clerestory, where the high windows were placed. The upper level was supported from the outside by the flying buttresses. This system was used at Noyon Cathedral, Sens Cathedral, and other early structures.

In the High Gothic period, thanks to the introduction of the four part rib vault, a simplified elevation appeared at Chartres Cathedral and others. The alternating piers and columns on the ground floor were replaced by rows of identical circular piers wrapped in four engaged columns. The tribune disappeared, which meant that the arcades could be higher. This created more space at the top for the upper windows, which were expanded to include a smaller circular window above a group of lancet windows. The new walls gave a stronger sense of verticality and brought in more light. A similar arrangement was adapted in England, at Salisbury Cathedral, Lincoln Cathedral, and Ely Cathedral.

An important characteristic of Gothic church architecture is its height, both absolute and in proportion to its width, the verticality suggesting an aspiration to Heaven. The increasing height of cathedrals over the Gothic period was accompanied by an increasing proportion of the wall devoted to windows, until, by the late Gothic, the interiors became like cages of glass. This was made possible by the development of the flying buttress, which transferred the thrust of the weight of the roof to the supports outside the walls. As a result, the walls gradually became thinner and higher, and masonry was replaced with glass. The four-part elevation of the naves of early Cathedrals such as Notre-Dame (arcade, tribune, triforium, clerestory) was transformed in the choir of Beauvais Cathedral to very tall arcades, a thin triforium, and soaring windows up to the roof.

Beauvais Cathedral reached the limit of what was possible with Gothic technology. A portion of the choir collapsed in 1284, causing alarm in all of the cities with very tall cathedrals. Panels of experts were created in Sienna and Chartres to study the stability of those structures. Only the transept and choir of Beauvais were completed, and in the 21st century, the transept walls were reinforced with cross-beams. No cathedral built since exceeded the height of the choir of Beauvais.