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Encaustic Tile

At present, the design community along with the public refers to Encaustic Tiles as those tiles that have a repeat pattern on them, rather than referring to the actual production method. With this “modern definition”, these tiles can be either authentic colored clay impressions, porcelain or other materials that are encaustic “lookalike” tiles. What is important for the installer is to be able to discern between a porcelain or pressed ceramic tile that has been made with an “encaustic” design and a true encaustic tile. A true encaustic tile that does not meet the ANSI A 137.1 requirements may have characteristics that will require much more installation diligence and caution. These tiles may not be able to be installed per ANSI A108 standards.

The following information is to inform you about true encaustic tiles so you can attempt to decipher the difference between them and other materials that may have an “encaustic design” and what cautions to take when dealing with a true encaustic tile.

For a better understanding encaustic tiles, the following article from Flash Point , the Quarterly Report of the Tile Heritage Founda tion, Vol 1, No. 4, Oct.-Dec. 1988 follows:

According to the Funk & Wagnell’s New International Dictionary the word “encaustic” is derived from the Latin “encausticus” and from the Greek “enkaustikos” “en” meaning in and “kaiein” to burn, to burn in. From Glazed Expressions, the No. 10 , the bi-annual publications of Tiles & Architectural Ceramics Society: The word “encaus tic” is derived from a peculiar technique of ancient Greek art ists for producing burnt-in designs using wax. “Egkausis” was the art of this burnt-in encaustic painting. The ancient Greeks spelled such words as “egk- “but pronounced them as “Enk” … The Egkaustike techne” (art of technique) used by “egkaustai” (encaustic painters) for producing “egkaumata” (encaustic pic tures) by means of tools called “egkausteria” was well estab lished by Plato’s day. But had nothing to do with inlaid ceramic tiles. According to David Hamilton in The Thames and Hudson Manu al of Architectural Ceramics , there are three basic methods for producing encaustic tiles: Encaustic tiles are traditionally made of red-burning clay pressed into a tile frame and stamped with an image which produces recesses in the surface of the tile. This series of depressions is then filled with white clay in a liq uid or very soft state so as to overfill the hollows. The tile is left in the frame to harden to a leather-hard state when the white clay is scraped or planed away to produce a flat tile with a white image integrated into the body. The impressed image may be built up to several die stamps where this is more convenient. It is possible to extend the ap parent printing technique so that the image is produced by sev eral impressions each in it’s turn filled with a clay of a different color. An alternative method is to produce an open-topped mold with the image intended for the face of the tile in relief on the bottom. The clay is cast as a thin layer allowed to stiffen and

then backed up by pressing plastic clay into the mold. When leather-hard, the tile is removed and the hollows on the face of the tile filled with clay of a contrasting color. When this is leath er-hard, the surface of the tile is planed level. Dust-pressed encaustic tiles were made by producing the inlay as a separate pressing locating it in the bottom of the press and backing up with tile dust. Several methods of shaping the col ored inlay, where used, from bent wire frames soldered together in the shape of the image to pierced metal plates. In every case the inlay was first lightly pressed, the frame removed, the inlay put in the die, pressed and then fired.

Encaustic and solid color geometric tiles manufactured by the U.S. Encaustic Tile Company, installed in the Stewart Mansion, Audubon, Iowa in 1891

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NTCA Reference Manual | 2024 / 2025

Chapter 5 | Material Specific Products and Installation