Guastavino tile

Guastavino tile is the "Tile Arch System" patented in the United States in 1885 by Valencian (Spanish) architect and builder Rafael Guastavino (1842–1908).

Guastavino vaulting is a technique for constructing robust, self-supporting arches and architectural vaults using interlocking terracotta tiles and layers of mortar to form a thin skin, with the tiles following the curve of the roof as opposed to horizontally (corbelling), or perpendicular to the curve (as in Roman vaulting). This is known as timbrel vaulting, because of supposed likeness to the skin of a timbrel or tambourine. It is also called "Catalan vaulting" and "compression-only thin-tile vaulting".

Guastavino tile is found in some of New York’s most prominent Beaux-Arts landmarks and in major buildings across the United States.

The Guastavino terracotta tiles are standardized, less than an inch (25 mm) thick, and approximately 6 inches (150 mm) by 12 inches (300 mm) across. They are usually set in three herringbone-pattern courses with a sandwich of thin layers of Portland cement. Unlike heavier stone construction, these tile domes could be built without centering. Each tile was cantilevered out over the open space, relying only on the quick drying cements developed by the company. Akoustolith, a special sound absorbing tile, was one of several trade names used by Guastavino.

Guastavino tile has both structural and aesthetic significance.

Structurally, the timbrel vault was based on traditional vernacular vaulting techniques already very familiar to Mediterranean architects, but not well known in America. Terracotta free-span timbrel vaults were far more economical and structurally resilient than the ancient Roman vaulting alternatives.

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