A separate consensus body, the national grading rule committee ngrc is established to develop and maintain nomenclature and descriptions of grades for dimension lumber that conform to this standard. Dimension lumber grades are divided into the following classifications. The grading rules are published in the western lumber grading rules book. Ninety percent of the minimum widths mentioned in all grades of lumber shall be full width. Agencies inspect the products from all mills regularly to ensure that the grades are accurate. Lumber grades take into account natural characteristics, including knots, splits, checks, shake, and wane. In contrast most export markets are more familiar with a metric standard. Structural light framing 2x2 through 4x4, used where highstrength design values are required in light framing sizes, such as in engineered wood trusses. It is a process of growth and expansion to meet the necessities of varying. This rule also applies to each stock width and to any specified width. Grows exclusively in the pacific northwest between the vast stands of softwood timber such as.
No meet director can lift in there own meet that they are suppose to be either directing or codirecting. Worldwide, hardwood lumber producers grade their lumber, assuring downstream consumers of the lumber of the lumber s quality for the intended use. Other western lumber species western wood products. Select filtering categories below to locate resource materials by resource usage, topic, product, or species. The grade of hardwood lumber is determined by a visual inspection of each board according to rules developed by the national hardwood. Other than the fas grades, the grade of the board is determined from the percentage of these clear cuttings and do not consider defects outside of the clear areas. Log grading relation to lumber grading most hardwood logs are sawn into lumber. Ngr portion of wwpa rules for douglas fir, larch, and spfs. A spiralbound book of the full nlga standard grading rules for canadian lumber may be purchased from nlga through our publication sales section of the website. To ensure that the product meets a written standard, an agency grading rule paragraph or equivalent grade should be referenced. Nhla grading rules national hardwood lumber association. That can change plans for how its used on the job site. Put simply, lumber grading serves quality assurance needs.
The national lumber grades authority nlga is the organization responsible for the establishment, issuance, publication, amendment and interpretation of canadian lumber grading rules and standards. Nlga is the only recognized rules writing body for lumber grades and standards in canada. Width of the piece is determined at the narrowest point in the standard length with a sawn edge. Each piece of dimension lumber is inspected to determine its grade and a stamp is applied indicating the assigned grade, the mill identification number, a green sgrn or dry s. Third party grading agencies regularly inspect the products from all mills to make sure that they are on grade. When lumber is used as finish trim it should be ordered in an appearance grade. The nhla lumber grading rules adopted by the us hardwood industry are based on an imperial. In addition to grading the quality of the lumber, lumber grading associations also report the moisture content at the time the wood was turned into lumber surfaced. The american softwood lumber standard ps 20 established the national grading rule for dimension lumber covering the thicknesses of 2. A spiralbound book of the full nlga standard grading rules for canadian lumber may be purchased from nlga through our publication sales section of the. The major characteristics encountered in grading of softwood lumber are listed for. Grading agencies redwood grading rules, the standard specifications for grades of california redwood lumber, are developed and published by the redwood inspection serviceris. Ps 20 provides for a national grading rule ngr for dimension lumber 1 with simplified grade names and sizes to assure uniformity, efficiency and economy in the use of dimension lumber. Additionally, the rules were developed with random width and length lumber in mind.
Under the auspices of the alsc is the national grading rule, which specifies grading characteristics for different grade specifications. Canadian dimension lumber is manufactured in accordance with csa o141 softwood lumber and must conform to the requirements of the canadian and us lumber grading rules. Grading rule establishes standard lumber grades and grade names, assuring users of. Pdf files of sections of the standard grading rules for canadian lumber are listed below. Those standards are then enforced by regional associations. The bureau publishes grading rules under which more than 95% of the production of the entire industry is classified and sold. Dimensional lumber western wood products association. Publications for download national lumber grades authority. Understanding framing lumber grades pro construction guide. Machine stress rated msr lumber is evaluated by mechanical stress rating equipment. Spf s grademarked products may originate from either region and be graded either by or according to grading rules published by wwpa, the west coast lumber inspection bureau wclib, or the northeastern lumber manufacturers association nelma. See table 2 or spib grading rules for design values. Using spf dimension lumber in fine woodworking projects. Rules for which grading rules writing agencies is authorized.
Grading lumber is also sold according to its grade. Grade stamps applied to lumber surfaced to less than standard size shall show the size in the stamp. The spf rule book southern powerlifting federationworld bench and powerlifting associationrules and regulations, updated 62111 general rules 1. Wood handbookchapter 6lumber stress grades and design.
The national grading rule applies to all species of softwood lumber1 which are covered by grading rules. Written interpretations of these rules have been prepared by the national lumber grades authority in order to promote the uniform application of these rules. Chapter 7 stress grades and design properties for lumber, round timber, and ties national grading rule stress grading under the auspices of the alsc is applied to many sizes and patterns of lumber that meet the american softwood lumber standard provision. However, most stressgraded lumber is dimension lumber standard 38 mm. Additionally, the grade rules were developed with random width and length lumber.
Spf lumber is graded in the same way in all parts of canada, according to the rules written by the national lumber grades authority nlga. Before we get into the different grades of lumber, lets take a look at the various defects you may find in a piece of lumber common lumber defects. Each piece of wood is graded by national standards developed by the u. Its membership accounts for approximately 60% of the total production of southern pine.
The grade of the product knotty governs its overall quality. Spf stud grade is usually stronger than the standard grade and would take more weight before breaking if used in areas like joists. Spf lumber is graded identically, according to the rules of the national lumber grades authority nlga. Resources include product and technical support literature, grade rules, and design tools used to support design, specification, and application of western lumber. Lumber design values are assigned to lumber grades to provide a means for using this material in structural applications. The canadian lumber grading system is a transparent regulatory system that provides ongoing assurance to the designer, user and public that the lumber is of the quality as indicated on the product mark or grade stamp. Approved to supervise glued and machine graded lumber. The value of this lumber, and thus of the log, is determined in part by the lumber grade. Woodframe construction can last as long as a buildings occupants need, and many have stood for hundreds of years. Explore the use of the common grades to achieve the most value considering lumber cost and yield. Learning to grade softwood dimension lumber spib blog. Lumber is graded using the american lumber standards, which are based on the structural integrity of a board.
Refer to wrcla specification literature or grading rule books for available grades. We are pleased to provide free pdf sections of the nlga standard grading rules for canadian lumber 2017 edition for your personal reference. Most of the information in this course is based on information from one of the largest of those lumber producing associations, the. Includes product support literature, grade rules, and design tools used to support.
All lumber is graded in compliance with the nlga national lumber grades authority and the ngr national grading rules. Under these rules, grade stamping is restricted chiefly to yard grades of west coast lumber, such as finish, paneling, casing, base, flooring, ceiling, siding, stepping, boards, dimension, decking and timbers, which are graded under current rules of the west coast lumber inspection bureau. All subscribing mills listed here are authorized to grademark their lumber under spib. The ngr was incorporated in the spib standard grading rules for southern pine lumber, published by the southern pine inspection bureau. Spf s design values make it appropriate for general framing applications. Complete guide to buying lumber the art of manliness. The simplified process of determining hardwood lumber grades. The grade as stamped shall signify that the lumber conforms to the grade, size and seasoning provisions of these rules unless otherwise noted on the stamps. Ngr portion of wwpa rules for douglas fir, larch, and spf s 2. Lumber grading rules spib southern pine inspection bureau. The interpretations of these rules are vested in the national lumber grades authority. A copy of the interpretations are included at the back of this grade rule book for your convenience. This is the lumber generally used for framing construction, and it includes all the twoby lumber from two by fours up to two by 12s, as well as some of the oneby material one by twos up to one by 12s.
American softwood lumber standard dimension lumber in this thickness range is required to conform to the national grading rule, except for special products such as scaffold planks. This is important to know because as a piece of softwood lumber dries, it shrinks. The hardwood grading rules are quite complex and require study. To know what the grades mean you need to know which lumber associations rules are being applied, but as a typical example, select shop might mean cutting 70% clear both sides or 70% b or better on one side, with the percentage clear dropping to 50% for no. The provisions of this document apply to all softwood lumber species manufactured in. Please note that, effective march 1, 2019, supplements to the nlga standard grading rules have been posted on this website under publications updates. Hardwood lumber grading explained the simplified process. For complete details the grading rule book can be purchased from the national hardwood lumber. Guide to the different lumber grades lampert lumber. The grade of each piece of lumber depends on the quality. The grading and measurement of hardwood lumber is not a simple matter and should not be undertaken lightly. For the most uptodate list of certified agencies contact. This inspection agency is alscapproved to provide mill supervisory services under the ngr, its own, and the wclib and wwpa grading rules and to supervise machine. The nlga grade rule incorporates the national grading.
Lumber grade is the quality control standard of various kinds of lumber in the country. A lumber grade is the qualitycontrol standard for lumber that has been in place since such standards were instituted in 1960, following a revision to canadian and u. The rules for the inspection of lumber are uniform in construction and application but also carry with them the element of stability. Allowable stress ratings are published for each grade, and vary by species or species mix, as are evidenced in span tables. The common grades are likely to be most suitable for the cabinet industry, most furniture parts and flooring.
The nhla hardwood grading rules are the product of the process of evolutionary development and that process is still in operation. Box 210 germantown, maryland 208750210 rules for which grading rules writing agencies is authorized. A full description of a given stud grade would be something like 2x4 7858 stud grade s pf, or 2x6 7858 stud grade s pf. If you take a stroll through your local lumberyard or the lumber department of your big box home center, youll find several rows of spf dimension lumber. No rules or regulations can be truly effective unless. Organizations that write and publish grading rule books containing stress grade descriptions are called rules writing agencies. Lumber is graded based on the quality and appearance of the wood. Measurement the nhla grades are determined on an imperial measurement system using inches and feet. Grade stamps applied to boards and dimension lumber 4. These depend on various factors like the type of wood used and the number and types of defects, if any. Southern pine forests are some of the most productive and sustainable timberlands in the world, capturing large amounts of carbon from the air and storing it in lumber used every day. The nhla lumber grading rules adopted by the us hardwood industry are based on an imperial measurement system using inches and feet. In canada, the national lumber grades authority nlga is responsible for the establishment of canadian lumber grading rules and standards and publishes the ngr in the nlga standard grading rules. Msr lumber is distinguished from visually stress graded lumber in that each piece is nondestructively tested.
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