Ceramic & Stone Close Up: A solid endorsement for concrete tiles
By now it's clear that concrete is, and will remain, one of the most popular construction products. And, why not? It has consistently proven to be one of the strongest, most durable building products ever seen. Its use pre-dates the Romans who used it to erect the Roman Coliseum.
Interestingly, floor tiles crafted from concrete have been around just as long and have had many applications of note. For example, the Los Angeles City Hall and the Reagan National Airport in Washington D.C., rely on concrete tile. For its part, the Walt Disney organization even ships concrete tile all over the world for use in its overseas operations. Another notable installation was recently seen in L.A.'s historic Roosevelt Hotel.
The venerable building, which hosted the first Academy Awards in 1929, is listed in the National Register of Historic Places. As such, all new building materials must meet strict historical requirements. This meant that the company contracted to refurbish the hotel, MKB Enterprises, needed to match the floor tiles crafted in the early 1900's and in use at the Roosevelt Hotel for 70 years.
Mission Tile West accepted the challenge. The Pasadena-based company selected the Artillo series of concrete paver tiles manufactured by Arto Brick of Gardena, Ca. The durable pavers used are 3/4" thick, manufactured from fiber reinforced concrete, and exceed 4200 psi. Equally important, the tiles exceeded the ADA and L.A. City requirement for slip resistance (C.O.F.). GTR Marble of Los Angeles handled phase one of the project and installed 15,000 sq. ft. in the thinset method using MAPEI's Ultra Contact.
Formed in 1988, the CTMA (Ceramic Tile Manufacturer's Association) has worked to elevate the profile of concrete tile and publishes the "Concrete Tales" newsletter in an effort to educate those involved in the selection of building material. CTMA has also established an intensive test program at Smith-Emery labs in Los Angeles to complete the CSI and four-part "contractor's" spec for the manufacturer and proper installation of concrete tile.
A decidedly versatile material, concrete tile takes many forms and is available in a variety of shapes, sizes, thickness, textures and colors. It can be left natural, polished like stone, colored and textured, shot blasted to expose aggregate, or even, inlaid with fossils or semi-precious stones. Sealers can provide a finish of matte, semi-gloss or high gloss.
Concrete tiles are either cast extruded, or ram pressed. Sizes range from panelized 4"x4" units up to 30"x30" units.
There are also a number of elements to keep in mind when installing concrete tile. These include:
• Substrates: Any substrate acceptable for ceramic tile or dimensional stone is acceptable for concrete tile.
• Processing: They must be installed according to manufacturer's recommendations and industry standards.
• Movement Joints: Joints must conform to current Tile Council of America, (TCA) "Handbook for the Installation of Ceramic Tile".
• Expansion and Contraction: Like many other products concrete tiles can be affected by temperature changes, and excessive moisture, (similar to quarry and Saltillo tiles). CTMA test reports, however, indicate that when concrete tiles are installed correctly, temperature and moisture do not hinder installation.
• Setting Products: Industry approved thin-setting or mortar-set are recommended. Exterior installations should be back buttered.
• Grouting: It is recommended to use a "quarry" grade (saltillo) of sanded grout. Carefully follow manufacturers' instructions. Do not over water the grout.
CTMA (800-970-CTMA, fax 714-535-0244), is available to provide a complete set of specifications including those involving product and tile assembly performance, as well as installation instructions for both thin-set and mortar set installation methods used by both trades and sealers and maintenance. Specifications are also available in the CSI format. The installation recommendations within these specifications conform to both ANSI and the TCA Handbook. Also, both Product and Tile Assembly test procedures (ANSI) with several additional, more severe, test procedures were developed through the joint efforts of Smith-Emery and the CTMA.
Clearly the never-ending goal of the CTMA and its membership is to stay top of the changing world of concrete as we move through the 21st century. In the CTIOA field report 75-3-1 (R-99) the institute addresses concrete tiles reaction to water. Concrete tile curing, for example, is a chemical process called "hydration" which utilizes water to obtain a high strength within 28 days. Under controlled factory conditions the curing period can be reduced to less than a week.
Keep in mind the phenomena of concrete tile expanding to the introduction of water which could in turn affect the bond. Luckily this condition is definitely the exception rather than the rule and - most do not ship tiles until they have reached sufficient curing levels but it is still wise to recognize the dynamics of this slight possibility.
Another CTIOA field report recommends 95 percent coverage and urges installers to make certain they support the edges and corners. Refer to the TCA handbook for large size tiles.
There is a wealth of information from these and other sources and it's a good idea to utilize this free material to familiarize your self with the installation of concrete tile. The enhanced quality control and better education is fueling greater acceptance of concrete tile. And, that is turn means greater opportunities for flooring retailers/contractors. Be prepared when the opportunity arrives.