This rule also applies to each stock width and to any specified width. 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. Spf s design values make it appropriate for general framing applications. Additionally, the grade rules were developed with random width and length lumber. 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. Ngr portion of wwpa rules for douglas fir, larch, and spfs. However, most stressgraded lumber is dimension lumber standard 38 mm.
To ensure that the product meets a written standard, an agency grading rule paragraph or equivalent grade should be referenced. The nhla lumber grading rules adopted by the us hardwood industry are based on an imperial. Lumber design values are assigned to lumber grades to provide a means for using this material in structural applications. The national grading rule applies to all species of softwood lumber 1 which are covered by grading rules developed and approved under ps 20. 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. Structural light framing 2x2 through 4x4, used where highstrength design values are required in light framing sizes, such as in engineered wood trusses. Resources include product and technical support literature, grade rules, and design tools used to support design, specification, and application of western lumber. Spf lumber is graded identically, according to the rules of the national lumber grades authority nlga. Other western lumber species western wood products. Log grading relation to lumber grading most hardwood logs are sawn into lumber. Written interpretations of these rules have been prepared by the national lumber grades authority in order to promote the uniform application of these rules. Pdf files of sections of the standard grading rules for canadian lumber are listed below. The rules for the inspection of lumber are uniform in construction and application but also carry with them the element of stability. It is a process of growth and expansion to meet the necessities of varying.
The nhla lumber grading rules adopted by the us hardwood industry are based on an imperial measurement system using inches and feet. 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. The provisions of this document apply to all softwood lumber species manufactured in. These depend on various factors like the type of wood used and the number and types of defects, if any. Nlga is the only recognized rules writing body for lumber grades and standards in canada. Measurement the nhla grades are determined on an imperial measurement system using inches and feet. That can change plans for how its used on the job site. The hardwood grading rules are quite complex and require study. The grading rules are published in the western lumber grading rules book. Green building material southern pine consists of four main species longleaf, loblolly, shortleaf and slash. Grade stamps applied to lumber surfaced to less than standard size shall show the size in the stamp. Refer to wrcla specification literature or grading rule books for available grades. The spf rule book southern powerlifting federationworld bench and powerlifting associationrules and regulations, updated 62111 general rules 1.
All subscribing mills listed here are authorized to grademark their lumber under spib. The nlga grade rule incorporates the national grading. The major characteristics encountered in grading of softwood lumber are listed for. For the most uptodate list of certified agencies contact. Grade stamps applied to boards and dimension lumber 4. 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.
Grading rule establishes standard lumber grades and grade names, assuring users of. Lumber is graded based on the quality and appearance of the wood. Those standards are then enforced by regional associations. The grade of each piece of lumber depends on the quality. Approved to supervise glued and machine graded lumber. For complete details the grading rule book can be purchased from the national hardwood lumber. All lumber is graded in compliance with the nlga national lumber grades authority and the ngr national grading rules. In contrast most export markets are more familiar with a metric standard. Explore the use of the common grades to achieve the most value considering lumber cost and yield. Dimension lumber grades are divided into the following classifications. 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. The bureau publishes grading rules under which more than 95% of the production of the entire industry is classified and sold. Each piece of wood is graded by national standards developed by the u.
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. Worldwide, hardwood lumber producers grade their lumber, assuring downstream consumers of the lumber of the lumber s quality for the intended use. Nhla grading rules national hardwood lumber association. Additionally, the rules were developed with random width and length lumber in mind.
Msr lumber is distinguished from visually stress graded lumber in that each piece is nondestructively tested. 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. A copy of the interpretations are included at the back of this grade rule book for your convenience. Width of the piece is determined at the narrowest point in the standard length with a sawn edge. Please note that, effective march 1, 2019, supplements to the nlga standard grading rules have been posted on this website under publications updates. American lumber standard committee 7470 new technology way, suite f frederick, md 21703. Under the auspices of the alsc is the national grading rule, which specifies grading characteristics for different grade specifications. 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. 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. 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. 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. No meet director can lift in there own meet that they are suppose to be either directing or codirecting. The grading and measurement of hardwood lumber is not a simple matter and should not be undertaken lightly.
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. Dimensional lumber western wood products association. Grows exclusively in the pacific northwest between the vast stands of softwood timber such as. Lumber grading rules spib southern pine inspection bureau. Grading agencies redwood grading rules, the standard specifications for grades of california redwood lumber, are developed and published by the redwood inspection serviceris. Publications for download national lumber grades authority. Lumber grades take into account natural characteristics, including knots, splits, checks, shake, and wane. The simplified process of determining hardwood lumber grades. 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.
Rules for which grading rules writing agencies is authorized. 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. Lumber is graded using the american lumber standards, which are based on the structural integrity of a board. See table 2 or spib grading rules for design values. 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. Organizations that write and publish grading rule books containing stress grade descriptions are called rules writing agencies. 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. The ngr was incorporated in the spib standard grading rules for southern pine lumber, published by the southern pine inspection bureau. This is important to know because as a piece of softwood lumber dries, it shrinks. Wood handbookchapter 6lumber stress grades and design. Select filtering categories below to locate resource materials by resource usage, topic, product, or species. The grade of the product knotty governs its overall quality. Allowable stress ratings are published for each grade, and vary by species or species mix, as are evidenced in span tables.
Understanding framing lumber grades pro construction guide. Machine stress rated msr lumber is evaluated by mechanical stress rating equipment. Most of the information in this course is based on information from one of the largest of those lumber producing associations, the. 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. The grade of hardwood lumber is determined by a visual inspection of each board according to rules developed by the national hardwood. The nhla hardwood grading rules are the product of the process of evolutionary development and that process is still in operation. 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. Its membership accounts for approximately 60% of the total production of southern pine. We are pleased to provide free pdf sections of the nlga standard grading rules for canadian lumber 2017 edition for your personal reference. 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 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. 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. Includes product support literature, grade rules, and design tools used to support. Ninety percent of the minimum widths mentioned in all grades of lumber shall be full width.
Third party grading agencies regularly inspect the products from all mills to make sure that they are on grade. The common grades are likely to be most suitable for the cabinet industry, most furniture parts and flooring. Hardwood lumber grading explained the simplified process. When lumber is used as finish trim it should be ordered in an appearance grade. The interpretations of these rules are vested in the national lumber grades authority. Guide to the different lumber grades lampert lumber. The american softwood lumber standard ps 20 established the national grading rule for dimension lumber covering the thicknesses of 2. Using spf dimension lumber in fine woodworking projects. Spf stud grade is usually stronger than the standard grade and would take more weight before breaking if used in areas like joists. Complete guide to buying lumber the art of manliness. The value of this lumber, and thus of the log, is determined in part by the lumber grade. Box 210 germantown, maryland 208750210 rules for which grading rules writing agencies is authorized. Grading lumber is also sold according to its grade.
Learning to grade softwood dimension lumber spib blog. No rules or regulations can be truly effective unless. 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. 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.
Agencies inspect the products from all mills regularly to ensure that the grades are accurate. 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. Put simply, lumber grading serves quality assurance needs. Woodframe construction can last as long as a buildings occupants need, and many have stood for hundreds of years.