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Grades and Specifications Contents Introduction APA The Engineered Wood Association PRODUCT GUIDE GRADES AND SPECIFICATIONS CONTENTS INTRODUCTION Introduction ................................................................................................. 3 This guide to APA – The Engineered Wood Key Definitions ............................................................................................. 4 Association panel grades and specifications is APA Trademark........................................................................................ 4 meant to serve as a useful reference source for Product Standard PS 1-83 ........................................................................ 4 APA Performance Standards ..................................................................... 5 structural wood panel users, specifiers, Grade ...................................................................................................... 5 Exposure Durability ................................................................................. 5 dealers and distributors. It contains key Species Group Number............................................................................ 7 information about the many structural wood Span Ratings ............................................................................................ 7 panel grades produced by APA member mills, APA Performance Rated Panels...................................................................... 9 including APA Performance Rated Panels, APA Rated Siding.......................................................................................... 11-13 sanded plywood, and specialty grades. APA Sanded and Touch-sanded Plywood ...................................................... 14-15 It illustrates and explains APA trademarks. APA Specialty Grades.................................................................................... 16 It provides a comprehensive guide to Guide to Specifications ................................................................................. 17-20 architectural specifications. And it contains panel installation recommendations for Storage and Handling.................................................................................... 21 typical construction applications. Installation ................................................................................................... 21-22 For complete panel application Method of Ordering...................................................................................... 23 recommendations or additional product Grade Availability.......................................................................................... 23 information, consult any of the other APA Additional Information.................................................................................. 23 publications cited throughout this brochure. Or for additional specification or design About APA ................................................................................................... 24 assistance, contact the nearest APA regional field office listed on the back cover. APA trademarked structural wood panels. For the very best in versatility, durability and quality…in hundreds of construction, industrial and do-it-yourself applications. APA – The Enginnered Wood Association ©1995 KEY DEFINITIONS APA TRADEMARK U.S. PRODUCT Panels conforming to the product The APA – The Engineered Wood STANDARD PS 1-83 standard carry the notation “PS 1-83” in Association’s trademarks appear only on U.S. Product Standard PS 1-83 for the lower portion of the APA trademark. products manufactured by APA member Construction and Industrial Plywood is a For a complete copy of U.S. Product mills. The marks signify that the voluntary commodity standard developed Standard PS 1-83 for Construction and manufacturer is committed to APA’s cooperatively by the U.S. Department of Industrial Plywood, Form H850, write the rigorous program of quality inspection Commerce and the construction and APA – The Engineered Wood Association. and testing and that panel quality is industrial plywood industry. PS 1-83 subject to verification through APA audit establishes requirements for producing, – a procedure designed to assure marketing and specifying construction and manufacture in conformance with APA industrial plywood. With the exception of performance standards and/or U.S. Plyron and some APA Performance Rated Product Standard PS 1-83 for Construction Panels, all of the other plywood and Industrial Plywood. grades described in this guide Unsanded and touch-sanded panels, are produced under the and panels with “B” or better veneer on provisions of U.S. Product one side only, usually carry the APA trade- Standard PS 1-83. mark on the panel back. Panels with both sides of “B” or better veneer, or with special overlaid surfaces (such as Medium Density Overlay), carry the APA trademark on the panel edge. 3 TYPICAL APA APA PERFORMANCE of veneer permitted in Exterior plywood is TRADEMARKS STANDARDS “C.” “D” veneer is used only in panels APA performance standards are the result intended for interior use or for of manufacturing technology that makes applications protected from permanent possible the manufacture of structural exposure to the weather. Panel panel products from wood by-products grade APA Span RATED STURD-I-FLOOR and species not provided for in U.S. EXPOSURE DURABILITY Rating 23/32 INCH Thickness 24 oc Product Standard PS 1-83. APA perfor- APA trademarked panels may be Tongue- SIZED FOR SPACING and-groove T&G NET WIDTH 47-1/2 mance standards deal exclusively with produced in four exposure durability EXPOSURE 1 Exposure how a product must perform in a desig- classifications – Exterior, Exposure 1, durability 000 Mill classification PS 1-83 UNDERLAYMENT number nated application rather than from what or Exposure 2, and Interior. The exposure PRP-108 Product how the product must be manufactured. durability classification relates to glue Standard Panels produced under APA performance bond, and thus to structural integrity. standards – called APA Performance Rated Since aesthetic (non-structural) attributes Panels – must meet several performance Panel of panels may be compromised to some grade APA baseline requirements according to the degree by exposure to weather(2), RATED SHEATHING Span panel’s designated end use. These perfor- Rating 15/32 INCH Thickness installation recommendations in this 32/16 mance requirements include uniform and publication are designed to provide SIZED FOR SPACING Exposure EXPOSURE 1 concentrated static and impact load optimum overall performance. durability Mill classification 000 capacity, fastener-holding ability, racking Exterior panels have a fully PRP-108 number HUD-UM-40C resistance, dimensional stability, and waterproof bond and are designed for APA’s Performance-Rated bond durability. applications subject to permanent Panel Standard In addition to conventional veneer exposure to the weather or to moisture. plywood, APA performance standards encompass such other panel products as Panel APA APA APA Siding grade RATED SHEATHING RATED SIDING face grade composites and oriented strand board. 303-18-S/W 48/24 23/32 INCH A-C GROUP 1 Span Thickness Rating 11/32 INCH (See APA Performance Rated Panels, SIZED FOR SPACING 24 oc GROUP 1 Species page 8.) EXTERIOR EXTERIOR SIZED FOR SPACING group 000 000 Exposure EXTERIOR number PS 1-83 C-C durability For complete performance testing and PRP-108 PS 1-83 Mill classification 000 PS 1-83 FHA-UM-64 number qualification information, write APA for PRP-108 HUD/FHA PRP-108, Performance Standards and recognition Exposure 1 panels have a fully Product Standard Policies for Structural-Use Panels, water-proof bond and are designed for Form E445. applications where long construction Exposure delays may be expected prior to providing GRADE Face durability protection, or where high moisture veneer classification The term “grade” may refer to panel grade conditions may be encountered in service. or to veneer grade. Panel grades are gen- A-B • G-1 • EXPOSURE 1-APA • 000 • PS1-83 Exposure 1 panels are made with the same erally identified in terms of the veneer exterior adhesives used in Exterior panels. Back Species Mill Product grade used on the face and back of the veneer group number Standard However, because other compositional number panel (e.g., A-B, B-C, etc.), or by a name factors may affect bond performance, only suggesting the panel’s intended end Exterior panels should be used for use (e.g., APA Rated Sheathing, permanent exposure to the weather.(3) Underlayment, etc.). Veneer grades define veneer appearance in terms of natural unrepaired growth APA APA RATED SHEATHING 15/32 INCH characteristics and allowable number and 32/16 A-D GROUP 1 SIZED FOR SPACING size of repairs that may be made during EXPOSURE 1 EXPOSURE 1 manufacture. The highest quality veneer is 000 000 PRP-108 PS 1-83 “A,”(1) the lowest “D.” The minimum grade HUD-UM-40C 4 VENEER GRADES Smooth, paintable. Not more than 18 neatly made repairs, boat, sled, or router type, and parallel to grain, permitted. A Wood or synthetic repairs permitted. May be used for natural finish in less demanding applications. Solid surface. Shims, sled or router repairs, and tight knots to 1 inch across grain permitted. Wood or synthetic repairs B permitted. Some minor splits permitted. Improved C veneer with splits limited to 1/8 inch width and knotholes or other open defects limited to 1/4 x 1/2 inch. C Admits some broken grain. Wood or synthetic repairs Plugged permitted.
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