Masonry Magazine June 1979 Page. 17
cells. Furring tile, nominal thickness 2 in., in ceramic glaze often referred to as "soaps", are produced with either solid backs or open (ribbed) backs. If either vertical-cell or horizontal-cell units are required for specific locations, this should be stated in the project specifications. Similarly, if solid-back soaps or furring are required, it should be so stated. Otherwise, product specifications make the selection optional with the supplier.
Plaster Base Finish. Specifications for structural clay facing tile and structural clay tile contain requirements for the finish of surfaces suitable for the application of plaster. When such surfaces are required, they should be specified in the project specifications; otherwise, the finish of the un-exposed (back) of the unit is optional with the supplier.
Tests. Most ASTM specifications for structural clay products provide that the cost of tests of units furnished for any particular project "shall be borne by the purchaser", unless the tests indicate that the units do not conform to the requirements of the specifications, in which case "the cost shall be borne by the seller". Project specifications should state the number of tests that will be required and should indicate who is responsible for selecting the samples and who pays the cost of testing.
PROJECT SPECIFICATIONS FOR STRUCTURAL CLAY PRODUCTS
As previously indicated, it is recommended that ASTM specifications, supplemented to meet project requirements, be used in specifying brick and structural clay tile. These specifications are suitable for use in any of the following forms:
Open Specifications. This type of specification, frequently required in public work, makes no reference to product trade names. In such a specification, ASTM specifications should be included by reference, supplemented with project requirements, and an "approved sample" of the required color and texture should be available for inspection by bidders prior to submission of bids.
Trade Names. For private work, specifying facing brick and structural facing tile by trade or manufacturer's names gives the contractor definite information as to the product required and pro-vides the architect with assurance that the quality desired will be furnished.
In general, when this method is used, three or more acceptable products are named and the contractor is given the option of selecting among them.
When trade names are used for specifying brick or tile, it is recommended that the units be required to comply with applicable ASTM specifications and that samples of acceptable units be available for inspection of bidders prior to bidding; also, that a provision for substitution, similar to that previously recommended, be included in the specifications.
Allowances. The use of allowances for cost of facing brick and facing tile has been used success-fully for many years and, in general, this method is recommended by the Structural Clay Products Institute. Allowances place all contractors on an equal basis and permit the owner to select products that he considers most desirable. However, when this method is employed, the specifications should state the size and texture of the units that will be selected, the tests that will be required and the responsibility for payment of tests.
GUIDE SPECIFICATIONS
The guide specifications in Technical Notes 11A Revised and 11B Revised are written for both reinforced and non-reinforced brick masonry, designed to comply with ANSI A41.1-1953 (R1970), "Building Code Requirements for Masonry". ANSI A41.2-1960 (R1970), "Building Code Requirements for Reinforced Masonry", or equivalent sections in the Model Building Codes.
The guide specifications in these Technical Notes can be used for engineered brick masonry designed to comply with Building Code Require-ments for Engineered Brick Masonry, SCPI, August 1969, or equivalent sections in the Model Building Codes, when additional quality assurance require-ments are incoporated into the specification. See Technical Notes 11C Revised.
The specifications do not cover requirements for structural clay tile, concrete masonry units, glass block or stone. Where these materials and design procedures are included in the masonry section, the specifications should be supplemented or revised. It will be found, however, that many of the requirements pertaining to brick masonry are also applicable to other types of masonry construc-tion.
"Guide Specifications for Masonry Mortar" will be included as a separate Technical Notes 11E to comply with CSI format.
Metric numbers listed are conversions from the current customary system and are not industry agreed-upon standards; i.e., a typical modular 3½ x 2% x 7½-in. (actual size) brick may be produced at some dimensions other than 89 x 57 x 191 mm when metric dimensions are adopted within the industry.
The cold weather protection requirements con-tained in paragraph 1.05.C are those recommended by the International Masonry Industry All-Weather Council, published December 1, 1970.