Slate An excerpt from the Dimension Stone Design Manual, Version VIII (May 2016) Produced and Published by the Marble Institute of America 380 East Lorain St. Oberlin, Ohio 44074 Telephone: 440-250-9222 Fax: 440-774-9222 www.naturalstoneinstitute.org © 2016 All rights reserved. No part of this document may be reproduced or transmitted in any form or by means electronic or mechanical, including photocopy, recording, or by an information storage and retrieval system, without written permission from the Natural Stone Institute. SLATE 1.2.3.1 Membership, Products, and Services Directory 1.0 GENERAL 1.2.3.2 Dimension Stone Design Manual 1.1 Related Documents 1.2.3.3 Additional publications may be available from the MIA Bookstore. Go online 1.1.1 Drawings and general provisions, at www.marble-institute.com. including General and Supplementary Conditions of the Contract and Division I 1.3 Scope of Included Work Specification sections, apply to this section. 1.3.1 The work to be completed under this 1.2 Applicable Publications contract includes all labor and materials required for the furnishing and installation of 1.2.1 The following publications listed here all slate work shown or called for on the and referred to thereafter by alphanumeric contract drawings, specifications, and code designation only, form a part of this addenda. specification to the extent indicated by the references thereto: 1.4 Definition of Terms 1.2.2 ASTM International (ASTM): 1.4.1 The definitions of trade terms used in this specification shall be those published by the 1.2.2.1 C629, Standard Specification for MIA or ASTM International. Slate Dimension Stone 1.5 Source of Supply 1.2.2.2 C120, Standard Test Methods of Flexure Testing of Slate (Modulus of Rupture, 1.5.1 All slate shall be obtained from quarries Modulus of Elasticity) having adequate capacity and facilities to meet the specified requirements, and by a firm 1.2.2.3 C121, Standard Test Method for equipped to process the material promptly on Water Absorption of Slate order and in strict accord with specifications. The Specifying Authority (architect, designer, 1.2.2.4 C217, Standard Test Method for engineer, contracting officer, end user, etc.) Weather Resistance of Slate reserves the right to approve the Material Supplier for slate prior to the award of this 1.2.2.5 C241, Standard Test Method for contract. Stone and workmanship quality shall Abrasion Resistance of Stone Subjected to Foot be in accordance with Industry Standards and Traffic Practices as set forth by the MIA. 1.2.2.6 C880, Standard Test Method for 1.6 Samples Flexural Strength of Dimension Stone 1.6.1 The Slate Contractor shall submit 1.2.2.7 C1353, Standard Test Method Using through the General Contractor, for approval the Taber Abraser for Abrasion Resistance of by the Specifying Authority, at least two sets of Dimension Stone Subjected to Foot Traffic samples of the various kinds of slate specified. The sample size shall be 1'-0" x 1'-0" and shall 1.2.3 Marble Institute of America represent approximately the finish, texture, (MIA): and anticipated range of color to be supplied. © 2016 Marble Institute of America Slate • Page 10-1 One set of samples shall be retained by the 1.8 Defective Work Specifying Authority, and one set shall be returned to the Slate Supplier for his/her 1.8.1 Any piece of slate showing flaws or record and guidance. It is noted herein that imperfections upon receipt at the storage yard slate is a natural material and will have intrinsic or building site shall be referred to the variations in color, markings, and other Specifying Authority for determination as to characteristics. Color variation range is to be responsibility and decision as to whether it shall only from natural markings in the slate or from be rejected, patched, or redressed for use. Any the reflective sheen and shadow value of the material in question should not be installed graining of the natural-cleft textures and prior to inspection and approval. cleavage planes. Depending on slate selected and quantity required, a range mockup may be 1.9 Repairing Damaged Stone used to further define the characteristics of the material. Cost of mockup, if required, shall not 1.9.1 Chips at the edges or corners may be be included in this section. patched, provided the structural integrity of the stone is not affected and the patch matches 1.6.2 Prior to fabrication, an inspection and the color and finish of the natural stone so that approval by the Specifying Authority and/or it does not detract from the stone’s General Contractor and/or End User of the appearance. finished slabs is recommended to understand the finish and full range of the material. 2.0 MATERIALS 1.7 Shop Drawings 2.1 Slate 1.7.1 The Slate Contractor shall submit through the General Contractor, for approval 2.1.1 General: All slate shall be of standard by the Specifying Authority, sufficient sets of architectural grade, free of cracks, seams, shop drawings showing general layout, starts, or other traits which may impair its jointing, anchoring, stock thickness, and other structural integrity or function. Inherent color pertinent information. These drawings shall variations characteristic of the quarry from show all bedding, bonding, jointing, and which it is obtained will be acceptable. Texture anchoring details along with the net piece and finish shall be as shown in the sample(s) dimensions of each slate unit. One copy of the approved by the Specifying Authority. approved shop drawings shall be retained by the Specifying Authority, one copy shall be 2.1.2 ASTM C629 [C120] [C121] [C217] retained by the General Contractor, and one [C241] See the chart of applicable ASTM copy returned to the Slate Contractor for standards and tests in the Appendix. fabrication. NO FABRICATION OF SLATE SHALL BE STARTED UNTIL SUCH 2.1.3 Schedule: Slate shall be provided as DRAWINGS HAVE BEEN FULLY follows: APPROVED AND MARKED AS SUCH. The Slate Contractor shall not be responsible for 2.1.3.1 For (state location on building) (state determining, making, or verifying (1) design, name and color) slate with a (type) finish, structural, wind, seismic, or other design supplied by (name company or list several approved loads; (2) engineering estimates; (3) plans or suppliers). specifications; (4) the types, sizes, or locations 2.1.3.2 Provide information as in (1) for of anchors; or (5) verification of field each different slate/finish combination in the dimensions, unless specifically added to the project. scope of work. Page 10-2 • Slate 2016 Marble Institute of America 2.1.4 Finishes: Face finish of all exterior 3.0 FABRICATION panels should be natural cleft. Sand-rubbed, honed and other finishes are available, 3.1 Dimensional Limitations depending on the Slate Supplier. All exposed edges should be honed to remove saw marks 3.1.1 Slate spandrels, panels, and wall facings and darken the edge color. are recommended in thicknesses of 1", 1¼", and sometimes 1½". Standard economical 2.1.4.1 Finishes listed in the schedule shall lengths are up to 6'-6" and widths up to 4'-0". conform with definitions by the MIA or ASTM Special larger sizes are available to meet design International. and job conditions on special request. No single piece is recommended to be over 9'-6" in 2.2 Setting Mortar length or 5'-0" in width. Larger sizes may be available only under special conditions and 2.2.1 Mortar for setting and pointing shall be limited production. one part portland cement and one part plastic lime hydrate to three to five parts of clean, 3.2 Beds and Joints nonstaining sand. It shall be mixed in small batches, using potable, non-alkaline water with 3.2.1 Bed and joint width shall be determined a pH of 7, until it is thoroughly homogeneous, by analysis of anticipated building movements stiff, and plastic. After mixing, the mortar shall and designed to accommodate such set for not less than one hour or more than two movements without inducing undue stresses in hours before being used. the stone panels or joint filler materials. Expansion joints shall be designed and located 2.3 Pointing Mortar to accommodate larger movements. 2.3.1 Mortar for pointing shall be Type N, as 3.2.2 Some slight lippage and variation is defined in ASTM C270 (Standard Specification natural and unavoidable where the natural-cleft for Mortar for Unit Masonry). All mixing, face comes together at the sawed joints. handling, and placing procedures shall be in accordance with ASTM C270. 3.2.3 Joints 3/8" or ½" are recommended between standard size panels, and ¼" and 3/8" 2.4 Sealants and Backup joints at abutting masonry. All joints are to be Material (If Applicable) water- and moisture-tight and caulked with a proper sealant. 2.4.1 Where specified, (state type or name of sealant) shall be used for the pointing of joints. 3.3 Backs of Pieces The backup material used with the sealant shall be (identify material) 3.3.1 Backs of pieces shall be sawn or roughly dressed to approximately true planes. Back surfaces shall be free of any matter that may 2.5 Anchors, Cramps, and create staining. Dowels 3.4 Moldings, Washes, and Drips 2.5.1 All wire anchors, cramps, dowels, and other anchoring devices shall be nonferrous 3.4.1 Moldings, washes, and drips shall be metal of the types and sizes shown on approved constant in profile throughout their entire shop drawings.