- THE MAGAZINE
Restoring mosaic ceramic floor tile preserves the character and beauty of the past.
Ceramic tile has been used for centuries in the decoration of commercial and residential buildings to add interest, style and character. Recently, there has been a renewed interest in preserving the character and beauty of the past, and old buildings are being restored and brought back into use. In addition to brick, plaster and woodwork, the original ceramic tile floors of these historic buildings are being uncovered, preserved and restored.
For the past 53 years, Winburn Tile has built and preserved the dies and produced the colors necessary to match original installations dating back to the early 1900s. The company traces its history to the Niloak Pottery of Benton, Ark., which manufactured unglazed, porcelain colored body houseware pottery from the Civil War era through the 1940s.
Niloak (the name is derived from the spelling of kaolin in reverse) used the Wilcox formation of clays that are deposited in central Arkansas. In the early 1940s, Hardy Winburn II acquired the assets of Niloak, and the company manufactured various ceramic products, including clay targets for the U.S. Army during World War II. Winburn Tile was founded in 1947 by combining those assets, which included buildings, kilns and various other manufacturing equipment, with used presses, dies and preparation equipment from The Mosaic Tile Co. of Zanesville, Ohio.
The result of this partnership was an unglazed mosaic tile manufacturing company. The original business was a manufacturing facility with the entire production dedicated to The Mosaic Tile Co. A significant part of the restoration dies used today are preserved from this early facility.
Today, Winburn is in its third generation of family ownership under the direction of Hardy Winburn V. Serving the commercial building market, the company’s primary product remains unglazed ceramic mosaic tile, manufactured in the widest range of colors available. Restoration is a small specialty portion of the current operation.
Embarking on a Restoration ProjectThere are two schools of thought when it comes to restoration of ceramic tile floors. Depending on the integrity of the existing tile installation, the options are to either patch or completely replace the floor using new tiles that match the original tile.
Because of the nature of restoration, the first option is always tried first. After all, restoration (and preservation) is the name of the game—the architect will attempt to preserve as much of the original installation as possible. Normally, only when the original sub-floor has deteriorated to a point where the building is unsafe or cannot be saved will the complete floor be replaced.
As a general rule, each restoration project presents its own set of problems and opportunities for creativity that must be dealt with by the architect, the tile supplier and the tile contractor. Often, economics is a major factor in privately owned buildings. Although the philosophy to preserve and patch is very strong, complete replacement is often a more cost-efficient alternative. The final floor will look the same, but a new installation is much easier and less expensive to install.
Generally, public buildings are much larger installations and require a combination of both types of restoration. Some large areas might be completely replaced, while other areas that are still viable and safe can be preserved.
Restoration from Start to FinishOnce the decision is made to either patch or replace the tile, a sample of the original tile is required. Using this tile, Winburn matches the color and cosmetic contamination present in the original floor.
The first requirement is always to match color. Laboratory trials are run using combinations of raw oxides and commercially prepared pigments. The company preserves a library of previous trials, including actual tile samples and formulations with firing data, so the color matching process phase normally takes only a few trials. Occasionally, the color has already been previously matched. Several different formulas and lots are often blended together to reproduce the shade variations found in the original installation. And contamination specks can be added from the company’s 53-color palette, if necessary, to match the original floor. After the color is matched, samples are produced for approval by the architect.
Once the samples have been approved, the first production runs are made. Die sizes and formulation changes affect the final tile size, and it is critical for patching that the tile size be as close as practical. If current dies cannot produce the required tile size, shrinkage tests are conducted and a new die is designed specifically for the project. The cost of a new die can play a big factor in the economics of a small restoration project.
The tile is hand pressed on friction presses from the original press department of Winburn. Original drawings of these old presses are dated 1922. The tile is also hand fettled to remove excess material. The thickness of the original floor must be matched when patching, and the new tile is often made slightly thinner to allow for binding to the original mortar bed. Originally, the tile was installed by beating the tile into a mortar bed, so thickness variation ended up on the bottom of the mortar bed. In a restoration project, the mortar bed is generally fixed. The tile must be manufactured to a relatively close tolerance since any variations will be exposed on the floor surface. Thickness is set and maintained by the press operator using a gauge and periodic adjustments to maintain consistency.
If possible, the restoration tile is formulated to fire in Winburn’s tunnel kilns along with the normal production—Cone 9 with a maximum temperature of 2240°F. In cases where special firing is required to reproduce a special color or effect, custom firing takes place off site at a neighboring ceramic facility.
Before installation, the original floor is stripped completely, removing decades of soapy water film, smoke, waxes, etc. Normally what is found is that the original tile looks the same as the day it was installed. Color has not faded, the tile is very hard and has aged beautifully, hidden under decades of maintenance patina.
Originally, the factory shipped bulk tiles to the contractor for mounting. But in the late 1940s, Winburn began mounting the tile into larger units or sheets, repeating any patterns present in the original floor. Using boards fashioned with separation steels between the tiles, employees place the tiles into the boards, inspect for chips and other defects, and then brush glue and perforated paper onto the back of the tile.
Mounting boards and visual inspection has not changed, but machinery was developed in the late 1950s to dot mount mosaics in a semi-automatic fashion, using small permanent plastic dots on the back edges of the tile. More and more automation has been added so that today, aside from the visual inspection of the individual tiles, the tiles are mounted automatically.
The manufacture of this tile requires tedious attention to detail by Winburn employees. While unglazed mosaic factories have been fully automated elsewhere, the experience and knowledge of how to produce these products by hand has been preserved at Winburn. New employees are apprenticed with experienced workers to preserve the knowledge necessary for production of these specialty products.