Figure 7-24.-Special tile-setting tools.corrosive conditions often encountered in industrial andcommercial installations. It may be applied over basesof wood, plywood, concrete, or masonry. This type ofmortar is nonshrinking and nonporous. A bond strengthof over 1,000 pounds per square inch is obtained withthis installation method.Organic AdhesivesOrganic adhesives (mastics) are applied in a thinlayer with a notched trowel. They are solvent-base,rubber material. Porous materials should be primedbefore mastic is applied to prevent some of theplasticizers and oils from soaking into the backing.Suitable surfaces include wood, concrete, masonry,gypsum wallboard, and plaster. The bond strengthavailable varies considerably among manufacturers, butthe average is about 100 pounds per square inch.GROUTSThe joints between the tiles must be filled with agrout selected to meet the tile requirements andexposure. Tile grouts may be portland cement base,epoxy base, furans, or latex.Cement grout consists of portland cement andadmixtures. This is better in terms of waterproofing,uniform color, whiteness, shrink resistance, and finetexture than a plain cement. It maybe colored and usedin all areas subject to ordinary use. When the grout isplaced, the tiles should be wet. Moisture is required forproper curing.Drywall grout has the same characteristics asdry-set mortar and is suitable for areas of ordinary use.Tiles to be set in drywall grout do not require wettingexcept during very dry conditions.Epoxy grout consists of an epoxy resin andhardener. It produces a joint that is stainproof, resistantto chemicals, hard, smooth, impermeable, and easy toclean. It is used extensively in counters that must be keptsanitary for foods and chemicals. It has the same basiccharacteristics as epoxy mortars.Furan resin grout is used in industrial areasrequiring high resistance to acids and weak alkalies.Special installation techniques are required with thistype of grouting.Latex grout is used for a more flexible and lesspermeable finish than cement grout. It is made byintroducing a latex additive into the Portland cementgrout mix.TOOLSA selection of special tools, shown in figure 7-24,should be available when doing tile installation work.7-21
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business