ASTM D245-22

Standard Practice for Establishing Structural Grades and Related Allowable Properties for Visually Graded Lumber

SIGNIFICANCE AND USE
3.1 Need for Lumber Grading:  
3.1.1 Individual pieces of lumber, as they come from the saw, represent a wide range in quality and appearance with respect to freedom from knots, cross grain, shakes, and other characteristics. Such random pieces likewise represent a wide range in strength, utility, serviceability, and value. One of the obvious requirements for the orderly marketing of lumber is the establishment of grades that permit the procurement of any required quality of lumber in any desired quantity. Maximum economy of material is obtained when the range of quality-determining characteristics in a grade is limited and all pieces are utilized to their full potential. Many of the grades are established on the basis of appearance and physical characteristics of the piece, but without regard for mechanical properties. Other grades, called structural or stress grades, are established on the basis of features that relate to mechanical properties. The latter designate near-minimum strength and near-average stiffness properties on which to base structural design.  
3.1.2 The development of this practice is based on extensive research covering tests of small clear specimens and of full-sized structural members. Detailed studies have included the strength and variability of clear wood, and the effect on strength from various factors such as density, knots (See Terminology D9), and other defects, seasoning, duration of stress, and temperature.  
3.2 How Visual Grading is Accomplished—Visual grading is accomplished from an examination of all four faces and the ends of the piece, in which the location as well as the size and nature of the knots and other features appearing on the surfaces are evaluated over the entire length. Basic principles of structural grading have been established that permit the evaluation of any piece of stress-graded lumber in terms of a strength ratio for each property being evaluated. The strength ratio of stress-graded lumber is the hypothet...
SCOPE
1.1 This practice (1, 2)2 covers the basic principles for establishing related unit stresses and stiffness values for design with visually-graded solid sawn structural lumber. This practice starts with property values from clear wood specimens and includes necessary procedures for the formulation of structural grades of any desired strength ratio.  
1.2 The grading provisions used as illustrations herein are not intended to establish grades for purchase, but rather to show how stress-grading principles are applied. Detailed grading rules for commercial stress grades which serve as purchase specifications are established and published by agencies which formulate and maintain such rules and operate inspection facilities covering the various species.  
1.3 The material covered in this practice appears in the following order:    
Section  
Scope  
1  
Significance and Use  
3  
Basic Principles of Strength Ratios  
4  
Estimation and Limitation of Growth Characteristics  
5  
Allowable Properties for Timber Design  
6  
Modification of Allowable Properties for Design Use  
7  
Example of Stress-Grade Development  
8  
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trad...

General Information

• Status: Published
• Publication Date: 31-Jan-2022
• ICS: 79.040 - Wood, sawlogs and sawn timber
• Technical Committee: D07 - Wood
• Drafting Committee: D07.02 - Lumber and Engineered Wood Products

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D245 − 22
Standard Practice for
Establishing Structural Grades and Related Allowable
1
Properties for Visually Graded Lumber
This standard is issued under the fixed designation D245; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope 1.6 This international standard was developed in accor-
2 dance with internationally recognized principles on standard-
1.1 This practice (1, 2) covers the basic principles for
ization established in the Decision on Principles for the
establishing related unit stresses and stiffness values for design
Development of International Standards, Guides and Recom-
with visually-graded solid sawn structural lumber. This prac-
mendations issued by the World Trade Organization Technical
tice starts with property values from clear wood specimens and
Barriers to Trade (TBT) Committee.
includes necessary procedures for the formulation of structural
grades of any desired strength ratio.
2. Referenced Documents
1.2 The grading provisions used as illustrations herein are 3
2.1 ASTM Standards:
not intended to establish grades for purchase, but rather to
D9 Terminology Relating to Wood and Wood-Based Prod-
show how stress-grading principles are applied. Detailed grad-
ucts
ing rules for commercial stress grades which serve as purchase
D143 Test Methods for Small Clear Specimens of Timber
specifications are established and published by agencies which
D2555 PracticeforEstablishingClearWoodStrengthValues
formulate and maintain such rules and operate inspection
E105 Guide for Probability Sampling of Materials
facilities covering the various species.
IEEE/ASTM SI-10 Practice for Use of the International
System of Units (SI) (the Modernized Metric System)
1.3 The material covered in this practice appears in the
following order:
3. Significance and Use
Section
Scope 1
3.1 Need for Lumber Grading:
Significance and Use 3
3.1.1 Individual pieces of lumber, as they come from the
Basic Principles of Strength Ratios 4
saw, represent a wide range in quality and appearance with
Estimation and Limitation of Growth Characteristics 5
Allowable Properties for Timber Design 6
respect to freedom from knots, cross grain, shakes, and other
Modification of Allowable Properties for Design Use 7
characteristics. Such random pieces likewise represent a wide
Example of Stress-Grade Development 8
range in strength, utility, serviceability, and value. One of the
1.4 The values stated in inch-pound units are to be regarded
obvious requirements for the orderly marketing of lumber is
as standard. The values given in parentheses are mathematical
the establishment of grades that permit the procurement of any
conversions to SI units that are provided for information only
required quality of lumber in any desired quantity. Maximum
and are not considered standard.
economy of material is obtained when the range of quality-
1.5 This standard does not purport to address all of the
determining characteristics in a grade is limited and all pieces
safety concerns, if any, associated with its use. It is the
are utilized to their full potential. Many of the grades are
responsibility of the user of this standard to establish appro-
established on the basis of appearance and physical character-
priate safety, health, and environmental practices and deter-
istics of the piece, but without regard for mechanical proper-
mine the applicability of regulatory limitations prior to use.
ties. Other grades, called structural or stress grades, are
established on the basis of features that relate to mechanical
properties. The latter designate near-minimum strength and
1
near-average stiffness properties on which to base structural
This practice is under the jurisdiction of ASTM Committee D07 on Wood and
is the direct responsibility of Subcommittee D07.02 on Lumber and Engineered
design.
Wood Products.
Current edition approved Feb. 1, 2022. Published March 2022. Originally
3
approved in 1926. Last previous edition approved in 2019 as D245–06(2019). DOI: For referenced ASTM standards, visit the ASTM website, www.astm.org, or
10.1520/D0245-22. contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
2
The boldface numbers in parentheses refer to references at the end of this Standards volume information, refer to the standard’s Document Summary page on
practice. the ASTM webs
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D245 − 06 (Reapproved 2019) D245 − 22
Standard Practice for
Establishing Structural Grades and Related Allowable
1
Properties for Visually Graded Lumber
This standard is issued under the fixed designation D245; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope
2
1.1 This practice (1, 2) covers the basic principles for establishing related unit stresses and stiffness values for design with
visually-graded solid sawn structural lumber. This practice starts with property values from clear wood specimens and includes
necessary procedures for the formulation of structural grades of any desired strength ratio.
1.2 The grading provisions used as illustrations herein are not intended to establish grades for purchase, but rather to show how
stress-grading principles are applied. Detailed grading rules for commercial stress grades which serve as purchase specifications
are established and published by agencies which formulate and maintain such rules and operate inspection facilities covering the
various species.
1.3 The material covered in this practice appears in the following order:
Section
Scope 1
Significance and Use 3
Basic Principles of Strength Ratios 4
Estimation and Limitation of Growth Characteristics 5
Allowable Properties for Timber Design 6
Modification of Allowable Properties for Design Use 7
Example of Stress-Grade Development 8
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information purposes only.only and are not considered standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
1
This practice is under the jurisdiction of ASTM Committee D07 on Wood and is the direct responsibility of Subcommittee D07.02 on Lumber and Engineered Wood
Products.
Current edition approved Oct. 1, 2019Feb. 1, 2022. Published November 2019March 2022. Originally approved in 1926. Last previous edition approved in 20112019 as
D245–06(2011).D245–06(2019). DOI: 10.1520/D0245-06R19.10.1520/D0245-22.
2
The boldface numbers in parentheses refer to references at the end of this practice.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D245 − 22
2. Referenced Documents
3
2.1 ASTM Standards:
D9 Terminology Relating to Wood and Wood-Based Products
D143 Test Methods for Small Clear Specimens of Timber
D2555 Practice for Establishing Clear Wood Strength Values
E105 Guide for Probability Sampling of Materials
IEEE/ASTM SI-10 Practice for Use of the International System of Units (SI) (the Modernized Metric System)
3. Significance and Use
3.1 Need for Lumber Grading:
3.1.1 Individual pieces of lumber, as they come from the saw, represent a wide range in quality and appearance with respect to
freedom from knots, cross grain, shakes, and other characteristics. Such random pieces likewise represent a wide range in strength,
utility, serviceability, and value. One of the obvious requirements for the orderly marketing of lumber is the establishment of grades
that permit the procurement of any required quality of lumber in any desired quantity. Maximum economy of material is obtained
when the range of quality-determining characteristics in a grade is limited and all pieces are utilized to their full potential. Many
of the grades are established on the basis of appearance and physical characteristics of the piece, but without regard for mechanical
properties. Other grades, called structural or stress grades, are established on the basis of feature
...