FOREWORD

This specification is primarily for tiles that provide a brick-like appearance when installed. One of the most important items is veneer tile installation is to provide expansion joints. Metal extrusions in the structure can often be used to provide these. (If aluminum is used, it shall be insulated from contact with mortar and veneer.) Exterior installations should have expansion joints (minimum 1/4 inch wide), not more than 16 feet apart in both directions. They shall be continued through the tile, mortar setting bed, reinforcing wire and kept free of mortar and grout. They shall be filled with an approved caulking compound, as close as possible to the color of the grout.

SPECIFICATION

1.   SCOPE: Furnish all labor, material, tools, equipment, transportation and services required to complete the installation of veneer tile work indicated on drawings and as specified herein. (List scope of work).

2.   WORK SPECIFIED IN OTHER SECTIONS

^**(a) All surfaces to receive veneer tile over wood or steel stud construction shall be left with a scratch coat applied to a thickness of not less than 1/4 inch nor more than 1/2 inch from the structural face. Scratch coat shall be mixed in the proportions of one part portland cement to three parts clean sharp graded sand.

Wood or steel studs shall be covered with one of the following waterproofing materials: 15 lb. asphalt saturated building felt; ASTM D266 or polyethylene sheeting 0.004 inches thick, ASTM C156.

Wire reinforcing shall be furred out 1/4 inch from the studs and shall be 3.4 galvanized metal lath or 2" x 2" -- 16/16 or 1 1/2" x 2" -- 16/13, ASTM A82 and A185.

^**(b) All concrete surfaces to receive veneer tile shall be heavily sandblasted to remove surface oil and slickened surface caused by forms of troweling.

^*%c) After concrete surfaces are sandblasted, they shall receive a dash coat mixed in proportions of one part portland cement to one and one-half parts sharp fine graded sand. Add one part of Anti-Hydro to five parts of water and in turn add this into dry mixed sand and cement to bring to proper consistency. Roughened surfaces shall be cleaned and well saturated with water prior to application of dash coat. The dash coat shall provide an irregular coating over the concrete in thicknesses varying from a minimum of 1/16 inch to a maximum of 1/4 inch

Maintain moisture by covering or repeated wetting, for a minimum of three (3) days, until cured to maximum hardness and bond. If a thicker application is needed, use a scratch coat as listed in Paragraph 2(a).

^**(d) Examination of Surfaces to Receive Veneer Tile. Representatives of the general contractor, plastering contractor and tile contractor firms shall test hardness of scratch coat or dash coat with hammer and chisel and agree to suitability before installation is started.

3. MATERIALS:

(a) Veneer Tile shall be of highest quality tiles of sizes and colors hereinafter specified, of size and patterns indicated on drawings. Veneer Tile shall be (state brand to be used) or approved equal. Tile shall be as perfect as it is possible to manufacture, and shall be certified satisfactory for intended use by the manufacturer. The colors and shades shall be reasonably uniform. The exposed face of the tile shall be a smooth even surface and uniform in texture without chips.

Tiles, as defined in ASTM C242, (Tile.--A ceramic surfacing unit,) shall comply with ANSI A137.1.

Manufacturers or suppliers of tiles not covered by ANSI A137.1 must furnish proof of the adequacy of their product.

(1) Size: All tiles shall be of uniform thickness and shall be (give size) size.

'(2) Colors: Shall be (state colors). All colors used in the work shall match approved samples.

(b) Portland Cement shall conform to ASTM C150, Type I or Type II.

(c) Hydrated Lime shall be for masonry purposes and conform to ASTM C207, Type S, plus the added requirement limiting the unhydrated exides to 8% maximum.

(d) Sand shall comply with "Method for Test for Organic Impurities in Sand for Concrete," ASTM Designation C40 and "Specifications for Aggregate for Masonry Mortar," ASTM Designation C144.

(e) Sand--Extra Fine shall conform to Ceramic Tile Institute CTI-70-6.

(f) Water free from any impurities that is injurious to the construction and shall be fit for human consumption.

(g) Grout shall be one part of graded extra fine sand added to each two parts of portland cement for natural colored grout, -- or grout shall be (state color and give names of manufacturers for colored grout).

(h) Pure Coat shall be pure portland cement mixed with water into a trowelable wet slurry.

(i) Mortar Setting Bed shall be mixed in the proportions of one part portland cement, one part hydrated lime, six parts of clean sharp sand.

(j) Sealant for expansion joints shall be (state color, type and manufacturer).

4. WORKMANSHIP:

Veneer tile shall be set and grouted by journeymen tile setters experienced in setting tile of this type under similar conditions

(a) At no time shall the mortar setting bed be over 3/4 inch thick. Apply a plumb scratch coat where necessary to establish this. Plumb scratch shall be mixed in the proportions of one part portland cement to four parts clean, sharp sand and shall be let to stand a minimum of twenty-four hours before applying the mortar bed. Maintain moisture in plumb scratch by covering or repeated wetting, continue until setting bed is applied or for three full days if setting bed is not applied prior to this.

(b) Apply, rod and float the mortar setting bed to a uniform plumb and level surface, allowing room for veneer to bring finished surface to required plane. Thickness of mortar shall be 1/4 inch to 3/4 inch as required, cut through the setting bed, back to the scratch coat, horizontally and vertically every twenty-four (24) inches.

(c) Before positioning, apply to each tile a layer of neat cement paste 1/32 inch to 1/16 inch thick. Neat cement shall also be applied, as a skim coat, to the setting bed and then tile pressed and beat in place to provide complete coverage between mortar bed and contact surface tiles without voids.

(d) Where they occur and at least every 16 feet in both directions in the structure, expansion joints or control joints shall be continued through the mortar bed, veneer tile, reinforcing wire and kept free of mortar and grout. These shall be filled with an approved caulking compound, as close as possible to the color of the grout.

(e) Fill all joints with grout. Compress and tool the grout in the joints so that it bonds with the setting bed and tile edges without voids. Joints shall be neat and flush with the surface of the tile.

(f) Promptly clean tile as work progresses so as to minimize final cleaning. Do not leave mortar scum or grout to dry on tile faces.

5. CURING:

(a) Final cleaning: All cement and grout shall be removed from the face of the tile; then, when clean, polish dry.

(b) Acid cleaning shall not be used on glazed tile. For unglazed tile acid cleaning shall not be done before 10 days after setting. Wet with water before cleaning with sulfamic acid solution. Protect all metal with grease. After acid cleaning, flush thoroughly with clean water.

Specification Writer Must Supply Information. "Specification Writer Must Include In Another Section. " 'Alternate Thin-Set Method (below).

ALTERNATE THIN-SET METHOD:

For this method, delete -- Paragraph 4(c) -- and replace as follows:
The exposed back of each tile shall be given a 1/16 inch thick buttercoat of the pure coat. Tile shall then be placed in position on tested thin-set portland cement mortar, or rubber latex portland cement mortar, freshly combed onto the mortar setting bed with a notched trowel. All combing must be done in a horizontal direction. Care shall be taken to cover the mortar with the backbuttered units before it has become glazed over from exposure to sun or wind. Units shall then be tamped firmly into place, true and even with the finished surface line or plane.