The Vaults of Sint-Theresia’s church in Dilbeek (Belgium): Tradition and Innovation in Tile Vaults in the 20th Century

Historically, tile vaults have been used in Mediterranean countries, such as Spain, south-east of France, and Italy. At the end of the 19th century, Rafael Guastavino (1842-1908) exported this technique to the United States, where he built thousands of vaults. This story is well-known. However, what it is not so well-known is the transmission of tile vaults to the rest of Europe. A new research project (2019-21) about the history of the construction of Belgian vaults has discovered that this technique was introduced in Belgium at the beginning of the 20th century, not only in churches, but also in museums, palaces and other representative buildings. There is no evidence of earlier tile vaults in the country, and the data suggest the importation of the system from France. In 1905 the French contractor Auguste Fabre patented his system in Belgium, followed by other patents by Charles Daussin and Ernest Sussenarie.
The company founded by Charles Daussin, was in charge of the construction of the vaults of the church of St. Theresa in Dilbeek. This church was built in 1938. Vaults had been traditionally used in historicist buildings, but in this church, the architect, Léonard Homez, was seeking for new and modern forms. Tile vaults were used, introducing also the innovations of Daussin’s patent (a layer of mortar over the extrados and metallic reinforcement), and combining it with a concrete structure. This paper analyses the construction and the geometry of the tile vaults of the St. Theresa Church in Dilbeek. It will also explain the context; the introduction of tile vaults in Belgium and the different innovations brought in. The analysis of the geometry and the brick bonding, that can be seen through the inner coat, will give an insight in the construction sequence. Homez had used tile vaults before in the churches of Divine Saviour in Schaerbeek (1935) and St. Alix in Woluwe-Saint-Pierre (1935-36), but in St. Theresa he used a much more complex geometry multiplying surfaces and groins in a way that departs from the historicist types and shows a transition to new shapes.
Since the sources for this research topic are very scarce, the main source is the building itself. For that reason, a geometric survey with a laser scanner and a thorough study of the constructive evidence have been carried out. This is contextualised with the analysis of Belgian patents regarding tile vaults developed during the first half of the 20th century, an analysis of the content of contemporary journals where the contractors of these vaults advertised their companies, and the construction treatises and manuals compiling the knowledge about vault construction.