rshuey
REGISTERED
That didnt take the PBA long...hahaMule said:
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30% reduction to Southern Pine Span Charts
- Thread starter Mule
- Start date
Paul Sweet
SAWHORSE
It's one thing if this is unique to Southern Pine, we can just change to Hem-Fir or S-P-F and save money. The scary thing is if this is a problem in all species, and SPIB just caught it first. It's hard to believe that the quality of wood could have deteriorated so much since strength values were last revamped in 1991.
Thanks Mule for the updates, please keep us informed as this progresses. I'd be most interested in a summary of the meeting on Thursday and contact info for comments.
My comments on this board are my opinion of what is at the root of this and carry no more insight or weight than that.
I'm not sure if it's the quality of the resource degrading or the quality of what is being allowed through. I mentioned that the rules regarding compression wood are weak, here is what the Nat'l Grade Rule has to say.
As a practical matter the first 12-20 growth rings are abnormal wood. When that was contained within a small juvenile core it probably wasn't that big a deal. When it becomes the majority of a small diameter sawlog it becomes a much higher proportion of the lumber produced. The grading rules are silent on juvenile wood. I'm not automatically opposed to fast grown improved trees unless we use diameter as the harvest point. If the fast grown tree is harvested at 25 years old and 12" diameter the majority of it will be juvenile wood. If it is allowed to continue to grow the mature wood is then being laid down over a larger diameter core and will produce much more board footage per year of good mature wood than a slow growth tree with a small juvenile core. One common but incorrect notion is that tight growth rings equate to strength. In the range of about 6-40 rings per inch proportion of latewood is the best predictor of strength. You can have tight rings with a high proportion of earlywood and still have unusually light, weak wood.
Mule, if I could have dinner with your friend my question would be "could you see a difference in the lumber that broke below design value?" If there was any visible telltale, which I believe there was, then that is what grading is all about... exclude that defect from the grade and the present design values will be true and stable.
I'm all for holding their feet to the fire and having the intent of the grading rules enforced. If strength reducing characteristics are allowed in any grade unchecked there is no point in grading at all.
My comments on this board are my opinion of what is at the root of this and carry no more insight or weight than that.
I'm not sure if it's the quality of the resource degrading or the quality of what is being allowed through. I mentioned that the rules regarding compression wood are weak, here is what the Nat'l Grade Rule has to say.
IMO this is practically unenforceable and goes unenforced. If we are seeing brash failures in otherwise well graded lumber this is the cause and this rule needs fleshing out and enforcement. There is no mention of this defect on my TP grading pocket card, the above was from the book, my SPIB card states compression wood not allowed in damaging form for the grade considered. This is not on the graders radar.
As a practical matter the first 12-20 growth rings are abnormal wood. When that was contained within a small juvenile core it probably wasn't that big a deal. When it becomes the majority of a small diameter sawlog it becomes a much higher proportion of the lumber produced. The grading rules are silent on juvenile wood. I'm not automatically opposed to fast grown improved trees unless we use diameter as the harvest point. If the fast grown tree is harvested at 25 years old and 12" diameter the majority of it will be juvenile wood. If it is allowed to continue to grow the mature wood is then being laid down over a larger diameter core and will produce much more board footage per year of good mature wood than a slow growth tree with a small juvenile core. One common but incorrect notion is that tight growth rings equate to strength. In the range of about 6-40 rings per inch proportion of latewood is the best predictor of strength. You can have tight rings with a high proportion of earlywood and still have unusually light, weak wood.
Mule, if I could have dinner with your friend my question would be "could you see a difference in the lumber that broke below design value?" If there was any visible telltale, which I believe there was, then that is what grading is all about... exclude that defect from the grade and the present design values will be true and stable.
I'm all for holding their feet to the fire and having the intent of the grading rules enforced. If strength reducing characteristics are allowed in any grade unchecked there is no point in grading at all.
Last edited by a moderator:
I wrote ALSC requesting info and comment instructions on this. They sent an info packet containing the request from SPIB, the test results and comments by FPL. The email below arrived today.
Board of Review
American Lumber Standard Committee, Incorporated
R.B. Parrish, Chairman P.O. Box 210
R.L. Ethington Germantown, Maryland 20875-0210
W.T. Hawks Telephone: 301.972.1700
T.D. Searles, President Fax: 301.540.8004
E-Mail: alsc@alsc.org
VIA E-MAIL
TO: ALSC MEMBERS & ALTERNATES & OTHER
INTERESTED PARTIES
FROM: THOMAS D. SEARLES
DATE: OCTOBER 31, 2011
SUBJ: BOARD OF REVIEW MEETING – JANUARY 5, 2012
As you may know the Board of Review will next meet on January 5, 2012. The Board requests that written submissions be made at least 10 days prior to January 5, 2012.
Thank you.
TDS:tw
cc: Board of Review Counsel
Board of Review
American Lumber Standard Committee, Incorporated
R.B. Parrish, Chairman P.O. Box 210
R.L. Ethington Germantown, Maryland 20875-0210
W.T. Hawks Telephone: 301.972.1700
T.D. Searles, President Fax: 301.540.8004
E-Mail: alsc@alsc.org
VIA E-MAIL
TO: ALSC MEMBERS & ALTERNATES & OTHER
INTERESTED PARTIES
FROM: THOMAS D. SEARLES
DATE: OCTOBER 31, 2011
SUBJ: BOARD OF REVIEW MEETING – JANUARY 5, 2012
As you may know the Board of Review will next meet on January 5, 2012. The Board requests that written submissions be made at least 10 days prior to January 5, 2012.
Thank you.
TDS:tw
cc: Board of Review Counsel
Here's the response from the NAHB
http://www.nbnnews.com/NBN/issues/2011-10-31/Codes+and+Standards/index.html
http://www.nbnnews.com/NBN/issues/2011-10-31/Codes+and+Standards/index.html
From the SBCA;
Southern Pine Lumber Design Value Restoration Conceptual Proposal
By the Lumber Design Value Task Group
November 2011
Standard Visually Graded Lumber Production – Lumber Design Value Proposal
For those lumber manufacturers that desire to be primarily focused on general lumber production, the default lumber visual grading and subsequent lumber design value assignment could be as proposed by SPIB or as a change to the Mixed Southern Pine grade.
This results in design values as defined in SPIB’s “Table 4 Southern Pine and Mixed Southern Pine Design Values” or as Mixed Southern Pine as found in Appendix A.
There is precedent for using Mixed Southern Pine based on Temple Inland’s approach for their Rome Georgia mill as found in Appendix B.
Enhanced Visually Graded – Lumber Design Value Proposal
For those lumber manufacturers that desire to gain greater value with respect to the forest lands from which they are buying logs, it is proposed that these lumber manufacturers are allowed to take a visual grading and/or related quality control action(s) that will assure that they can obtain higher design values from their lumber resource through standard visual grading techniques.
The goal of this proposal is to allow a pathway that any lumber manufacturer can pursue through implementing a higher degree of visual grading quality control, where the purpose is to provide greater assurance that the lumber they are producing can achieve and maintain the current design values for Southern Pine as found in the current SPIB 2002 Grading Rules for Southern Pine Lumber, Appendix A – Design Values and as shown in the current NDS Supplement in Appendix C. This enhanced Visual Grading process, as outlined below, can take form of:
1. Use the current dense grade rule concepts to extract lumber that meets the current visual grading system.
a. Dense has been defined as follows:
Dense Grain;Requires 6 rings/inch & 1/3 summerwood or 4 rings/inch & 1/2 summerwood
Exceptionally light weight pieces: Should not be placed in #2N grade and higher (Exceptionally light pieces contain less than 15% summerwood)
b. Modifications to this can be made to assure that lumber of the proper design values fits the current grading rules for:
i. Dense SS, Dense #1 and Dense #2, or
ii. SS, #1 and #2
c. Anything not meeting the regular SP grade classification system will fall into another grade category per the SPIB grade rules that will need to be written.
i. Low strength material would be separated into a new grade, e,g, “Open Grain.”
2. Strong consideration should be given to implementing some type of quality assurance program to confirm that the visual grading process is providing expected design values from the visual grading process being used.
a. This can take any form that provides a higher degree of assurance and reliability of visually graded design properties, when compared to the Standard Visually Graded Lumber Production.
b. Additional QC concepts that could be used include:
i. More frequent double checks on the visual grading process to ensure that open grain and dense selections are being made reliably.
ii. Periodic testing of visually graded material through some mechanical means (e.g., non-destructive MOE, simple non-destructive mechanical bending, etc.).
1. Data can correlate to and confirm that the lumber design values as designed by the applied lumber grade-mark are accurate.
iii. The lumber manufacturer will undertake _________ QA confirmation through _________ (QA means) on ___________ (on what frequency seems reasonable) by grade and size produced____________ (for what period based on the QC frequency).
Mechanically Graded Lumber Production
A lumber manufacturer can use any of the available non-destructive MSR or MEL machines available to grade lumber. See Appendix D for the resulting design values that could be produced.
Goals and Objectives of the Foregoing Conceptual Proposal
1. Consumers of structural lumber are buying lumber design values to use in standard structural engineering equations to provide resistance to applied loads.
2. Suppliers of the lumber need to be supplying reliable lumber design values that can be used by lumber buyers as specified for load carrying end use applications as defined through traditional engineering oriented lumber associations (e.g. AWC, CWC, etc.).
3. We need to provide a common sense pathway for lumber manufacturers to be able to:
a. Provide the market with confidence in the lumber design values they are providing.
b. Use their timber resource to their market advantage based on the design property value that the logs they are buying provide.
4. It is important to consider as we go through this process that:
a. Rather than eliminating density classification as has been proposed by SPIB, density classification should be required for all visually graded SYP.
b. Full in-grade testing should be performed on all density classes of all sizes prior to any design value changes.
c. This last point is reinforced by the highlighted section of SPIB’s report below:
Next Steps
As of November 8, 2011, we believe with a reasonable degree of certainty, that the following concepts are currently being worked through:
1. A general agreement has been reached that developing an approach to define grade rules for lumber that would be classified as “Open Grain” has many positive attributes for the current conditions all collective lumber related industries find themselves in.
2. SPIB, Mississippi State University (maybe also Michigan Tech) and Timber Products Inspection are working on the grading rules that can be implemented inside the lumber manufacturing industry’s current process and procedures.
3. The SPIB and Mississippi State data is being used to define the “Open Grain” grading process and presumably how this fits into the current Southern Pine and Mixed Southern Pine system.
4. A first cut “Open Grain” grading proposal will be provided for review and discussion at the forthcoming SFPA meeting in Atlanta, GA, November 15th and 16th.
a. This will include the concepts surrounding the current Southern Pine and Mixed Southern Pine grades.
b. It is expected that the Atlanta meeting will define the next steps needed to finalize a comprehensive proposal that can be positively embraced by SPIB and its process.
c. Then additional meetings will be held based on this foundation, quickly, to finalize a revised or new SPIB approach to SP lumber design values.
5. Any agreement will need to be finalized and SPIB will need to get this approved through the SPIB process and then through ALSC.
6. There has been discussion regarding this grading procedure being an interim step in between the original testing that SPIB has already undertaken and a broader and more thorough in-grade testing program that would fill out the testing matrix much like was performed roughly 30 years ago.
There is a very positive development. We believe that all lumber related industries stand to benefit from collaboration. Finally it is clear to us that:
1. There is justifiable concern over the:
a. Volume and value of “open grain” graded lumber on one side.
b. Devaluation of lumber stock for a log resource that can produce regular SP design values on the other side.
2. We firmly believe that both sides of this equation can be winners. Here’s how:
a. If the Structural Building Components Industry has reliable lumber properties and good resulting real world performance, it can design structural building products and components using those properties.
b. There is good value with lower design value lumber because in engineered applications there are many areas where the applied load resistance stresses needed are not high.
c. Creative component manufacturers with strong engineering acumen will find ways to use any material that has sound properties and allows them to be as competitive as the market allows.
3. Finally the SBC industry believes that creative and innovative lumber producers have the opportunity to get closer to their end use customers and use this situation as incentive for positive change. This may result in many changes in the way lumber design values are assigned to meet specific general and proprietary needs in the market.
4. The opportunity available is significant, but it will require hard work and continued strong collaboration between the lumber industry and the SBC industry along with all our collaborative industries.
Southern Pine Lumber Design Value Restoration Conceptual Proposal
By the Lumber Design Value Task Group
November 2011
Standard Visually Graded Lumber Production – Lumber Design Value Proposal
For those lumber manufacturers that desire to be primarily focused on general lumber production, the default lumber visual grading and subsequent lumber design value assignment could be as proposed by SPIB or as a change to the Mixed Southern Pine grade.
This results in design values as defined in SPIB’s “Table 4 Southern Pine and Mixed Southern Pine Design Values” or as Mixed Southern Pine as found in Appendix A.
There is precedent for using Mixed Southern Pine based on Temple Inland’s approach for their Rome Georgia mill as found in Appendix B.
Enhanced Visually Graded – Lumber Design Value Proposal
For those lumber manufacturers that desire to gain greater value with respect to the forest lands from which they are buying logs, it is proposed that these lumber manufacturers are allowed to take a visual grading and/or related quality control action(s) that will assure that they can obtain higher design values from their lumber resource through standard visual grading techniques.
The goal of this proposal is to allow a pathway that any lumber manufacturer can pursue through implementing a higher degree of visual grading quality control, where the purpose is to provide greater assurance that the lumber they are producing can achieve and maintain the current design values for Southern Pine as found in the current SPIB 2002 Grading Rules for Southern Pine Lumber, Appendix A – Design Values and as shown in the current NDS Supplement in Appendix C. This enhanced Visual Grading process, as outlined below, can take form of:
1. Use the current dense grade rule concepts to extract lumber that meets the current visual grading system.
a. Dense has been defined as follows:
Dense Grain;Requires 6 rings/inch & 1/3 summerwood or 4 rings/inch & 1/2 summerwood
Exceptionally light weight pieces: Should not be placed in #2N grade and higher (Exceptionally light pieces contain less than 15% summerwood)
b. Modifications to this can be made to assure that lumber of the proper design values fits the current grading rules for:
i. Dense SS, Dense #1 and Dense #2, or
ii. SS, #1 and #2
c. Anything not meeting the regular SP grade classification system will fall into another grade category per the SPIB grade rules that will need to be written.
i. Low strength material would be separated into a new grade, e,g, “Open Grain.”
2. Strong consideration should be given to implementing some type of quality assurance program to confirm that the visual grading process is providing expected design values from the visual grading process being used.
a. This can take any form that provides a higher degree of assurance and reliability of visually graded design properties, when compared to the Standard Visually Graded Lumber Production.
b. Additional QC concepts that could be used include:
i. More frequent double checks on the visual grading process to ensure that open grain and dense selections are being made reliably.
ii. Periodic testing of visually graded material through some mechanical means (e.g., non-destructive MOE, simple non-destructive mechanical bending, etc.).
1. Data can correlate to and confirm that the lumber design values as designed by the applied lumber grade-mark are accurate.
iii. The lumber manufacturer will undertake _________ QA confirmation through _________ (QA means) on ___________ (on what frequency seems reasonable) by grade and size produced____________ (for what period based on the QC frequency).
Mechanically Graded Lumber Production
A lumber manufacturer can use any of the available non-destructive MSR or MEL machines available to grade lumber. See Appendix D for the resulting design values that could be produced.
Goals and Objectives of the Foregoing Conceptual Proposal
1. Consumers of structural lumber are buying lumber design values to use in standard structural engineering equations to provide resistance to applied loads.
2. Suppliers of the lumber need to be supplying reliable lumber design values that can be used by lumber buyers as specified for load carrying end use applications as defined through traditional engineering oriented lumber associations (e.g. AWC, CWC, etc.).
3. We need to provide a common sense pathway for lumber manufacturers to be able to:
a. Provide the market with confidence in the lumber design values they are providing.
b. Use their timber resource to their market advantage based on the design property value that the logs they are buying provide.
4. It is important to consider as we go through this process that:
a. Rather than eliminating density classification as has been proposed by SPIB, density classification should be required for all visually graded SYP.
b. Full in-grade testing should be performed on all density classes of all sizes prior to any design value changes.
c. This last point is reinforced by the highlighted section of SPIB’s report below:
Next Steps
As of November 8, 2011, we believe with a reasonable degree of certainty, that the following concepts are currently being worked through:
1. A general agreement has been reached that developing an approach to define grade rules for lumber that would be classified as “Open Grain” has many positive attributes for the current conditions all collective lumber related industries find themselves in.
2. SPIB, Mississippi State University (maybe also Michigan Tech) and Timber Products Inspection are working on the grading rules that can be implemented inside the lumber manufacturing industry’s current process and procedures.
3. The SPIB and Mississippi State data is being used to define the “Open Grain” grading process and presumably how this fits into the current Southern Pine and Mixed Southern Pine system.
4. A first cut “Open Grain” grading proposal will be provided for review and discussion at the forthcoming SFPA meeting in Atlanta, GA, November 15th and 16th.
a. This will include the concepts surrounding the current Southern Pine and Mixed Southern Pine grades.
b. It is expected that the Atlanta meeting will define the next steps needed to finalize a comprehensive proposal that can be positively embraced by SPIB and its process.
c. Then additional meetings will be held based on this foundation, quickly, to finalize a revised or new SPIB approach to SP lumber design values.
5. Any agreement will need to be finalized and SPIB will need to get this approved through the SPIB process and then through ALSC.
6. There has been discussion regarding this grading procedure being an interim step in between the original testing that SPIB has already undertaken and a broader and more thorough in-grade testing program that would fill out the testing matrix much like was performed roughly 30 years ago.
There is a very positive development. We believe that all lumber related industries stand to benefit from collaboration. Finally it is clear to us that:
1. There is justifiable concern over the:
a. Volume and value of “open grain” graded lumber on one side.
b. Devaluation of lumber stock for a log resource that can produce regular SP design values on the other side.
2. We firmly believe that both sides of this equation can be winners. Here’s how:
a. If the Structural Building Components Industry has reliable lumber properties and good resulting real world performance, it can design structural building products and components using those properties.
b. There is good value with lower design value lumber because in engineered applications there are many areas where the applied load resistance stresses needed are not high.
c. Creative component manufacturers with strong engineering acumen will find ways to use any material that has sound properties and allows them to be as competitive as the market allows.
3. Finally the SBC industry believes that creative and innovative lumber producers have the opportunity to get closer to their end use customers and use this situation as incentive for positive change. This may result in many changes in the way lumber design values are assigned to meet specific general and proprietary needs in the market.
4. The opportunity available is significant, but it will require hard work and continued strong collaboration between the lumber industry and the SBC industry along with all our collaborative industries.
Last edited by a moderator:
The reply screen got jumpy so I just started another post. The above was part of today's mailing. It also contained an xls file containing the results of their testing and an assessment of the SPIB testing. Some of the results were not good. The pieces with pith center were the worst with some >60% below NDS design values. It would be interesting to see results if they could test excluding everything from the first 10-12 growth rings.
From the LUMBER PRODUCERS COUNCIL
Press Release
November 11, 2011
FOR IMMEDIATE RELEASE
Contact: MSRLPC, (888) 848-5339 or info@msrlumber.org
MSR Lumber Design Values
Madison, WI – Recently, there have been design value changes proposed for some visual grades of
lumber. These decisions will have no impact on the design values of Machine Stress Rated (MSR)
lumber and Machine Evaluated Lumber (MEL) because of the way these products are manufactured and
tested.
Produced since the 1960s, MSR and MEL lumber have known and tested structural design values. In
contrast to visual grades, machine rated lumber is produced by measuring physical properties of
each piece of lumber in the production line. Manufacturers are required to test samples during each
shift and the entire quality assurance process is audited by independent third parties to confirm
conformance with the stated design values. MSR and MEL lumber consistently meet design value
requirements even as timber growing practices and environmental conditions change.
You can be confident in the strength and performance of MSR and MEL lumber. MSR/MEL lumber has
proven itself to be a cost-effective, quality lumber product for component manufacturers and
builders.
There are producers of MSR/MEL lumber across North America that can meet the needs of builders,
engineers, architects and all end-users. For more information on MSR and MEL lumber or to find a
producer near you, visit the MSR Lumber Producers Council website at www.msrlumber.org.
###
Press Release
November 11, 2011
FOR IMMEDIATE RELEASE
Contact: MSRLPC, (888) 848-5339 or info@msrlumber.org
MSR Lumber Design Values
Madison, WI – Recently, there have been design value changes proposed for some visual grades of
lumber. These decisions will have no impact on the design values of Machine Stress Rated (MSR)
lumber and Machine Evaluated Lumber (MEL) because of the way these products are manufactured and
tested.
Produced since the 1960s, MSR and MEL lumber have known and tested structural design values. In
contrast to visual grades, machine rated lumber is produced by measuring physical properties of
each piece of lumber in the production line. Manufacturers are required to test samples during each
shift and the entire quality assurance process is audited by independent third parties to confirm
conformance with the stated design values. MSR and MEL lumber consistently meet design value
requirements even as timber growing practices and environmental conditions change.
You can be confident in the strength and performance of MSR and MEL lumber. MSR/MEL lumber has
proven itself to be a cost-effective, quality lumber product for component manufacturers and
builders.
There are producers of MSR/MEL lumber across North America that can meet the needs of builders,
engineers, architects and all end-users. For more information on MSR and MEL lumber or to find a
producer near you, visit the MSR Lumber Producers Council website at www.msrlumber.org.
###
Below are some cut and pastes from a couple of the FPL's publications that I think help with understanding where we are with our forestry practices and wood quality. My personal feeling is that in the grading rules we need to expand the definition of compression wood to include all "reaction wood", juvenile, core, compression, and then enforce their exclusion when they do influence grade beyond the allowable limits of that grade. This would mean that the inner 10-12 rings would need to be boxed out into landscape timbers rather than included in structural lumber. This would hurt in the short term but would help direct our forestry practices into producing higher quality timber rather than reinforcing the production of maximum quantity of timber regardless of the quality. Lowering the design values is I think short sighted and counterproductive to where we really need to be heading.
Anecdotally, I was asked to come look at a log home job last week, there was a log sticking out of the stack that caused me to go take a look. It had reaction wood on one side and had bowed about 4". Unable to shrink on that face further it had cross grain timber breaks completely crossing perpendicular to the face. This stuff has no business in a house no matter how derated.
---
One of the major contributors to loss of quality in dimension lumber is excessive
longitudinal shrinkage. Intensive plantation forestry can greatly affect the growth
rate and percent latewood that is present in trees being managed. This difference in
growth rate directly impacts the structural performance of the lumber produced from
the trees. Rapid growth means that the juvenile wood core of a tree and its associated
inferior properties becomes a much larger proportion of the merchantable log.
This increase in juvenile wood core causes an increase in the frequency of
excessive shrinkage in dimension lumber (Larson et al. 2001). Longitudinal
shrinkage in juvenile wood can be 10 or more times greater than longitudinal
shrinkage in mature wood (Ying et al. 1994).
Bendtsen and Senft (1986) estimated the
juvenile period for loblolly pine to be 12 years based on
values for specific gravity, modulus of elasticity (MOE),
modulus of rupture (MOR), and compressive strength of the
wood. However, tracheid length continued to increase rapidly
for 18 years, and fibril angle had not yet attained a
constant value at 30 years.
slow growth does not eliminate juvenile wood but simply confines it to a
smaller core. Both narrow- and wide-core wood rings retain
their juvenile characteristics compared with narrow and wide
mature rings, respectively.
Growth ring width by itself, however,
provides no reliable evidence of wood quality. When sampled
at breast height (4 ft (1.2 m)), ring width usually increases
radially for an indefinite number of years before
either leveling off or decreasing. This pattern reflects both
growing conditions and proximity to the living crown. In
vigorous trees free of competition, wide rings will be produced
until the living crown advances upward beyond a
critical level. In trees from closely spaced stands where
competition is established early, ring widths are reduced
concomitant with the degree of competition. Thus, the radial
extent of the juvenile core cannot be estimated on the basis
of ring width patterns. Trees freed of competition by early
and frequent thinnings or whose growth is enhanced by
fertilization and cultivation can maintain wide growth rings
well beyond the generally accepted juvenile period. On the
contrary, trees subject to competition early in life might
exhibit narrow growth ring patterns suggestive of mature
wood.
During the early years of research on wood quality, beginning
about 1880, it was widely believed that slowly grown,
narrow-ringed wood of conifers was superior in quality to
that of rapidly grown, wide-ringed wood. In trees from the
naturally established stands prevalent at that time, most of
the wide rings occurred in the growth zone we now refer to
as juvenile wood. Silviculturists therefore recommended
planting trees at close spacings followed by frequent stand
thinning to maintain uniform ring widths. Most of this research
was based on data from natural stands and closely
spaced plantations in northern Europe (Larson 1962), although
similar recommendations were made for the southern
pines in the United States (Paul 1930, 1932a,b). Despite the
objections of some, these ideas prevailed until about 1950
when researchers, primarily in South Africa and Australia,
began examining fast-grown wood from wide-spaced plantation
trees. Results of this and later research proved that
growth ring width, per se, was not a valid criterion for
evaluating wood quality. The research also demonstrated
that close initial spacing of trees simply masked the effects
of juvenile wood by confining these growth rings to a small
core of wood near the pith where their influence on structural
properties was minimized.
Anecdotally, I was asked to come look at a log home job last week, there was a log sticking out of the stack that caused me to go take a look. It had reaction wood on one side and had bowed about 4". Unable to shrink on that face further it had cross grain timber breaks completely crossing perpendicular to the face. This stuff has no business in a house no matter how derated.
---
One of the major contributors to loss of quality in dimension lumber is excessive
longitudinal shrinkage. Intensive plantation forestry can greatly affect the growth
rate and percent latewood that is present in trees being managed. This difference in
growth rate directly impacts the structural performance of the lumber produced from
the trees. Rapid growth means that the juvenile wood core of a tree and its associated
inferior properties becomes a much larger proportion of the merchantable log.
This increase in juvenile wood core causes an increase in the frequency of
excessive shrinkage in dimension lumber (Larson et al. 2001). Longitudinal
shrinkage in juvenile wood can be 10 or more times greater than longitudinal
shrinkage in mature wood (Ying et al. 1994).
Bendtsen and Senft (1986) estimated the
juvenile period for loblolly pine to be 12 years based on
values for specific gravity, modulus of elasticity (MOE),
modulus of rupture (MOR), and compressive strength of the
wood. However, tracheid length continued to increase rapidly
for 18 years, and fibril angle had not yet attained a
constant value at 30 years.
slow growth does not eliminate juvenile wood but simply confines it to a
smaller core. Both narrow- and wide-core wood rings retain
their juvenile characteristics compared with narrow and wide
mature rings, respectively.
Growth ring width by itself, however,
provides no reliable evidence of wood quality. When sampled
at breast height (4 ft (1.2 m)), ring width usually increases
radially for an indefinite number of years before
either leveling off or decreasing. This pattern reflects both
growing conditions and proximity to the living crown. In
vigorous trees free of competition, wide rings will be produced
until the living crown advances upward beyond a
critical level. In trees from closely spaced stands where
competition is established early, ring widths are reduced
concomitant with the degree of competition. Thus, the radial
extent of the juvenile core cannot be estimated on the basis
of ring width patterns. Trees freed of competition by early
and frequent thinnings or whose growth is enhanced by
fertilization and cultivation can maintain wide growth rings
well beyond the generally accepted juvenile period. On the
contrary, trees subject to competition early in life might
exhibit narrow growth ring patterns suggestive of mature
wood.
During the early years of research on wood quality, beginning
about 1880, it was widely believed that slowly grown,
narrow-ringed wood of conifers was superior in quality to
that of rapidly grown, wide-ringed wood. In trees from the
naturally established stands prevalent at that time, most of
the wide rings occurred in the growth zone we now refer to
as juvenile wood. Silviculturists therefore recommended
planting trees at close spacings followed by frequent stand
thinning to maintain uniform ring widths. Most of this research
was based on data from natural stands and closely
spaced plantations in northern Europe (Larson 1962), although
similar recommendations were made for the southern
pines in the United States (Paul 1930, 1932a,b). Despite the
objections of some, these ideas prevailed until about 1950
when researchers, primarily in South Africa and Australia,
began examining fast-grown wood from wide-spaced plantation
trees. Results of this and later research proved that
growth ring width, per se, was not a valid criterion for
evaluating wood quality. The research also demonstrated
that close initial spacing of trees simply masked the effects
of juvenile wood by confining these growth rings to a small
core of wood near the pith where their influence on structural
properties was minimized.
This is from Timber Products Inspections;
Audited Stress Rating Program
Standard Operating Procedure
INTRODUCTION
These procedures allow a lumber manufacturer to establish higher Fb and E values for its finished product as compared to the published standards. Published Fb values derived from ASTM D1990 are based on a 75% confidence interval as a result of dividing the lower 5th percentile of the bending strength by a safety factor of 2.1. With a larger safety factor of 2.5 and increased qualification & daily QC sampling as compared with typical Machine Stress Rated QC procedures, it is possible for a mill to audit their visually graded production as described in these procedures and be able to label it accordingly if these procedures prove it to be superior.
Audited Stress Rating Program
Standard Operating Procedure
INTRODUCTION
These procedures allow a lumber manufacturer to establish higher Fb and E values for its finished product as compared to the published standards. Published Fb values derived from ASTM D1990 are based on a 75% confidence interval as a result of dividing the lower 5th percentile of the bending strength by a safety factor of 2.1. With a larger safety factor of 2.5 and increased qualification & daily QC sampling as compared with typical Machine Stress Rated QC procedures, it is possible for a mill to audit their visually graded production as described in these procedures and be able to label it accordingly if these procedures prove it to be superior.
This is from a lawyer representing the SBCA to the ALSC and interested parties;
Thomas D. Searles, PresidentAmerican Lumber Standard Committee, Inc.19715 Waters RoadGermantown, MD 20874Re: Southern Pine Inspection Bureau’s Proposed Changes in Design Values forVisually Graded Southern Pine Lumber (the “SPIB Proposal”) andImmediate Requested Action for the ALSC Board of Review (“Board”)Dear Mr. Searles:I am writing on behalf of the Structural Building Components Association (“SBCA”), which asyou know is an organization representing thousands of manufacturers of structural buildingcomponents and other industry participants, such as engineering and service companies,lumber mills, inspection bureaus, lumber brokers and distributors and related marketing andmanagement providers. SBCA has previously provided both testimony to the Board on October20, 2011 and follow-up written submissions, and will be providing additional written submissionslater this week in anticipation of the upcoming Board hearing date of January 5, 2012. SBCAalso plans to attend the January 5 hearing as it strongly opposes the SPIB Proposal, whichrequests ALSC approval allowing SPIB to publish new design values for all Southern Pinebased on a sampling and testing of a mere 360 pieces of 2x4 #2 Grade Southern Pine.The purpose of this letter is to request the Board take a relatively simple yet important actionbefore the end of this week. Assuming the Board has determined to go forward with theJanuary 5, 2012 hearing and act within 30 days after that hearing pursuant to Section 10.11 ofthe American Softwood Lumber Standard (the “Standard”),1SBCA requests the Board establisha set of written processes or procedures that fully set out how parties who may be affected byeither an approval or disapproval of the SPIB Proposal can have a further hearing before theBoard approval or disapproval becomes final. This request is clearly supported by the languageof Section 10.10 of the Standard, which was obviously designed to enable aggrieved parties theopportunity to fully and effectively appeal any Board decision before such decision becomesfinal.21Section 10.11 of the Standard reads: The Board shall within 30 days following an official action make such officialaction public.2Section 10.10 of the Standard reads: Any party affected by a decision or action of the Board shall have the right torequire the Board to hold a hearing at which such party may appear personally or be represented by counsel topresent supporting evidence and argument of the party’s position in accordance with procedures established by theBoard.
--------------------------------------------------------------------------------
Page 2
Searles, ThomasPage 2 of 2To accomplish the goals of Section 10.10, SBCA would suggest that the most appropriateprocedure for the Board to adopt would be to plan to announce a “proposed” rather than “final”decision following the January 5, 2012 hearing. The “proposed” decision and the reasoningbehind such decision would then be subject to the appeal or re-argument provisions of Section10.10. Under a specific set of written procedures announced by the Board, a subsequentappeal hearing could then be requested by a certain date and scheduled where additionalarguments could be heard and submissions made, either through counsel or otherwise. Anappeal could therefore be asserted by SBCA for example (or some other party) assuming theBoard approved the SPIB Proposal, or by SPIB assuming the Board rejected or otherwisepostponed action on the SPIB Proposal.3During the pendency of any appeal right or actualappeal, the Board’s procedures should further establish that SPIB hold in abeyance anypublication of a change of Southern Pine design values until after the parties had exhaustedtheir rights of appeal as established by the Standard. We believe this action is absolutelyrequired as SPIB seems poised to publish new design values immediately upon an approval bythe Board of the SPIB Proposal; see for example, http://www.southernpine.com/new-design-values.asp.4Assuming new design values are published (and further assuming an appeal rightor actual appeal was pending), borrowing from an idiom, it will be hard if not impossible to “putthis genie back in the bottle.”Based on the above, SBCA and its members request that the Board adopt the processes orprocedures we have outlined and announce the application of same by the close of business onDecember 23, 2011.Should you have any questions regarding our request, please feel free to contact me.Very Truly Yours,Kent J. Pagel3It does not appear that any party other than SPIB supports the SPIB Proposal, and thus no other party can beexpected to appeal a rejection on the part of the Board of the SPIB Proposal. On the other hand, multiple parties canbe expected to appeal a Board approval, in whole or in part, of the SPIB Proposal.4SBCA believes that upon an approval on the part of the Board of the SPIB Proposal, that SPIB will in turnimmediately publish new design values through Supplement No. 9 to the Southern Pine Inspection Bureau GradingRules 2002 Edition, which has already been prepared. This belief is based on the previous actions taken by SPIB asSupplement No. 8 was published effective August 1, 2011 and Supplement No. 10 was published effective October26, 2011. It is clear that SPIB anticipated that the Board would approve the SPIB Proposal at the hearing held onOctober 20, 2011 as Supplement No. 9 was prepared following approval of Supplement No. 8 (i.e., after August 1,2011) and prior to preparation and approval of Supplement No. 10 (i.e., before October 26, 2011).
Thomas D. Searles, PresidentAmerican Lumber Standard Committee, Inc.19715 Waters RoadGermantown, MD 20874Re: Southern Pine Inspection Bureau’s Proposed Changes in Design Values forVisually Graded Southern Pine Lumber (the “SPIB Proposal”) andImmediate Requested Action for the ALSC Board of Review (“Board”)Dear Mr. Searles:I am writing on behalf of the Structural Building Components Association (“SBCA”), which asyou know is an organization representing thousands of manufacturers of structural buildingcomponents and other industry participants, such as engineering and service companies,lumber mills, inspection bureaus, lumber brokers and distributors and related marketing andmanagement providers. SBCA has previously provided both testimony to the Board on October20, 2011 and follow-up written submissions, and will be providing additional written submissionslater this week in anticipation of the upcoming Board hearing date of January 5, 2012. SBCAalso plans to attend the January 5 hearing as it strongly opposes the SPIB Proposal, whichrequests ALSC approval allowing SPIB to publish new design values for all Southern Pinebased on a sampling and testing of a mere 360 pieces of 2x4 #2 Grade Southern Pine.The purpose of this letter is to request the Board take a relatively simple yet important actionbefore the end of this week. Assuming the Board has determined to go forward with theJanuary 5, 2012 hearing and act within 30 days after that hearing pursuant to Section 10.11 ofthe American Softwood Lumber Standard (the “Standard”),1SBCA requests the Board establisha set of written processes or procedures that fully set out how parties who may be affected byeither an approval or disapproval of the SPIB Proposal can have a further hearing before theBoard approval or disapproval becomes final. This request is clearly supported by the languageof Section 10.10 of the Standard, which was obviously designed to enable aggrieved parties theopportunity to fully and effectively appeal any Board decision before such decision becomesfinal.21Section 10.11 of the Standard reads: The Board shall within 30 days following an official action make such officialaction public.2Section 10.10 of the Standard reads: Any party affected by a decision or action of the Board shall have the right torequire the Board to hold a hearing at which such party may appear personally or be represented by counsel topresent supporting evidence and argument of the party’s position in accordance with procedures established by theBoard.
--------------------------------------------------------------------------------
Page 2
Searles, ThomasPage 2 of 2To accomplish the goals of Section 10.10, SBCA would suggest that the most appropriateprocedure for the Board to adopt would be to plan to announce a “proposed” rather than “final”decision following the January 5, 2012 hearing. The “proposed” decision and the reasoningbehind such decision would then be subject to the appeal or re-argument provisions of Section10.10. Under a specific set of written procedures announced by the Board, a subsequentappeal hearing could then be requested by a certain date and scheduled where additionalarguments could be heard and submissions made, either through counsel or otherwise. Anappeal could therefore be asserted by SBCA for example (or some other party) assuming theBoard approved the SPIB Proposal, or by SPIB assuming the Board rejected or otherwisepostponed action on the SPIB Proposal.3During the pendency of any appeal right or actualappeal, the Board’s procedures should further establish that SPIB hold in abeyance anypublication of a change of Southern Pine design values until after the parties had exhaustedtheir rights of appeal as established by the Standard. We believe this action is absolutelyrequired as SPIB seems poised to publish new design values immediately upon an approval bythe Board of the SPIB Proposal; see for example, http://www.southernpine.com/new-design-values.asp.4Assuming new design values are published (and further assuming an appeal rightor actual appeal was pending), borrowing from an idiom, it will be hard if not impossible to “putthis genie back in the bottle.”Based on the above, SBCA and its members request that the Board adopt the processes orprocedures we have outlined and announce the application of same by the close of business onDecember 23, 2011.Should you have any questions regarding our request, please feel free to contact me.Very Truly Yours,Kent J. Pagel3It does not appear that any party other than SPIB supports the SPIB Proposal, and thus no other party can beexpected to appeal a rejection on the part of the Board of the SPIB Proposal. On the other hand, multiple parties canbe expected to appeal a Board approval, in whole or in part, of the SPIB Proposal.4SBCA believes that upon an approval on the part of the Board of the SPIB Proposal, that SPIB will in turnimmediately publish new design values through Supplement No. 9 to the Southern Pine Inspection Bureau GradingRules 2002 Edition, which has already been prepared. This belief is based on the previous actions taken by SPIB asSupplement No. 8 was published effective August 1, 2011 and Supplement No. 10 was published effective October26, 2011. It is clear that SPIB anticipated that the Board would approve the SPIB Proposal at the hearing held onOctober 20, 2011 as Supplement No. 9 was prepared following approval of Supplement No. 8 (i.e., after August 1,2011) and prior to preparation and approval of Supplement No. 10 (i.e., before October 26, 2011).
The Board of Review sent out an email today. Basically they did agree to reduce the design values of SYP #2 2x4's at this time. Remember this was all based on the results of breaking about 200 #2 2x4's. They are requesting broader testing as soon as possible and are advising design professionals to bear the requested reductions in mind... some reduction is coming down the pike. SPF is under early scrutiny as well. It sounds like a new round of In Grade testing may be beginning.
jar546
CBO
Great updates DRP, this is most certainly appreciated
This is an article from the National Association of Home Builders.
Nation's Building News
The Official Online Newspaper of NAHB
FONT SIZE: A A A
Codes and Standards
Board Limits Changes to Southern Pine Design Values to 2x4s, Grade No. 2 and Lower
In response to comments from NAHB and a chorus of opposition from industry groups, the Board of Review of the American Lumber Standard Committee (ALSC) on Jan. 11 disapproved a proposal by the Southern Pine Inspection Bureau (SPIB) to lower design values for all grades and sizes of visually inspected Southern pine.
Instead, the board approved proposed new values for only 2x4, No. 2 lumber, which was the only size and grade the SPIB had tested before submitting its proposal on Oct. 6. In a supplemental ruling issued on Jan. 12, this was expanded to include all lower grades of 2x4s.
In addition, the review board approved a recommended effective date of June 1 for the new design values for 2x4s to "allow for their orderly implementation."
Prior to the hearing, SPIB had indicated that it intended, upon approval by the ALSC Board of Review, to immediately implement and publish the new design values in Supplment No. 9 to the 2002 Standard Grading Rules for Southern Pine Lumber.
Speaking before the Board of Review on Jan. 5, NAHB Chairman-elect Barry Rutenberg said that approval and immediate implementation of the proposal would cause chaos in the marketplace and result in an unjustified spike in lumber prices.
Rutenberg asked the board not to approve any change to the existing design values until SPIB completed testing of additional grades and sizes of Southern Pine lumber as required by ASTM D1990, the industry standard for establishing design values for visually graded lumber.
An effective date of June 1 provides the building industry nearly five months to implement the new design values for 2x4s.
The board also urged SPIB “to proceed with all deliberate haste” to complete the testing and analysis of additional grades and sizes of Southern Pine.
It is anticipated that the full matrix of in-grade tests will be completed in the summer, after which changes to the other grades and sizes of Southern Pine lumber may once again be proposed by SPIB.
NAHB has created a webpage — www.nahb.org/spdv — to provide information and additional resources on this issue.
For more information, email Gary Ehrlich at NAHB, or call him at 800-368-5242 x8545.
Nation's Building News
The Official Online Newspaper of NAHB
FONT SIZE: A A A
Codes and Standards
Board Limits Changes to Southern Pine Design Values to 2x4s, Grade No. 2 and Lower
In response to comments from NAHB and a chorus of opposition from industry groups, the Board of Review of the American Lumber Standard Committee (ALSC) on Jan. 11 disapproved a proposal by the Southern Pine Inspection Bureau (SPIB) to lower design values for all grades and sizes of visually inspected Southern pine.
Instead, the board approved proposed new values for only 2x4, No. 2 lumber, which was the only size and grade the SPIB had tested before submitting its proposal on Oct. 6. In a supplemental ruling issued on Jan. 12, this was expanded to include all lower grades of 2x4s.
In addition, the review board approved a recommended effective date of June 1 for the new design values for 2x4s to "allow for their orderly implementation."
Prior to the hearing, SPIB had indicated that it intended, upon approval by the ALSC Board of Review, to immediately implement and publish the new design values in Supplment No. 9 to the 2002 Standard Grading Rules for Southern Pine Lumber.
Speaking before the Board of Review on Jan. 5, NAHB Chairman-elect Barry Rutenberg said that approval and immediate implementation of the proposal would cause chaos in the marketplace and result in an unjustified spike in lumber prices.
Rutenberg asked the board not to approve any change to the existing design values until SPIB completed testing of additional grades and sizes of Southern Pine lumber as required by ASTM D1990, the industry standard for establishing design values for visually graded lumber.
An effective date of June 1 provides the building industry nearly five months to implement the new design values for 2x4s.
The board also urged SPIB “to proceed with all deliberate haste” to complete the testing and analysis of additional grades and sizes of Southern Pine.
It is anticipated that the full matrix of in-grade tests will be completed in the summer, after which changes to the other grades and sizes of Southern Pine lumber may once again be proposed by SPIB.
NAHB has created a webpage — www.nahb.org/spdv — to provide information and additional resources on this issue.
For more information, email Gary Ehrlich at NAHB, or call him at 800-368-5242 x8545.
MINUTES BOARD OF REVIEW March 9, 2012 The Board of Review continued its meeting in Executive Session on March 9, 2012, by conference call. The Board members present were Messrs. Parrish, Ethington and Hawks. Mr. Parrish chaired the meeting. Mr. Searles was present as Manager. Mr. Landry of Venable LLP was present as Counsel to the Board of Review. Messrs. McDaniel and Reck of the ALS staff, and Mr. David Kretschmann of FPL were also present. I. ANTITRUST STATEMENT Mr. Landry informed the group of their responsibilities under the antitrust laws. II. MINUTES OF LAST MEETING Chairman Parrish noted the minutes of the last meetings had been previously approved and distributed. III. SPIB SUBMISSION OF DESIGN VALUES FOR NO. 2 DENSE AND NO. 2 NON-DENSE 2 TO 4 INCHES THICK AND 2 TO 4 INCHES WIDE LUMBER The Board of Review initially considered the SPIB submission to assign design values to No.2 Dense 2 to 4 inches thick and 2 to 4 inches wide and No. 2 Non-Dense 2 to 4 inches thick and 2 to 4 inches wide southern pine at its meeting on February 23, 2012. On March 9, 2012, the Board continued its consideration of southern pine design values as submitted in the SPIB letters of January 23, 2012 and February 10, 2012, noting the FPL letters of January 25 and February 22, 2012. The Board noted that the design values previously approved by the Board on January 11, 2012 and as clarified by its Supplemental Ruling on January 12, 2012 apply to No. 2 and lower grades of 2" to 4" thick and 2" to 4" wide southern pine lumber and mixed southern pine species with an effective date of June 1, 2012. The Board reviewed the letter from the Structural Building Components Association that was received on January 28, 2012 and March 9, 2012. After consideration of all the information available to it, the Board approved the No.2 Dense 2 to 4 inches thick and 2 to 4 inches wide and No. 2 Non-Dense 2 to 4 inches thick and 2 to 4 inches wide southern pine design values as submitted by SPIB on February 10, 2012 with a recommended effective date of June 1, 2012.
Board of Review Minutes
March 9, 2012
Page 2
In granting the above approval the Board noted the following:
1. In the previous submission by SPIB, which was approved by the Board on
January 11, 2012, there was no differentiation between the design values for
No.2 Dense 2 to 4 inches thick and 2 to 4 inches wide and No. 2 Non-Dense 2 to
4 inches thick and 2 to 4 inches wide southern pine lumber.
2. There has been a historic recognition by the Board and by other respected
authorities that density of lumber contributes to its strength. The derivation of
the dense and non-dense values in the SPIB submission followed or improved on
procedures that have been used in previous submissions to the Board and in the
derivation of the original in-grade values. The new values are derived based
upon the latest test information and are not averages of past data. The Board
agrees with the SPIB statement that there was not enough data to assign design
values to all sizes and grades of southern pine lumber as originally proposed;
however, the Board also agrees that the use of the data from pieces actually
tested provides a conservative value for No. 2 Dense and No. 2 Non-Dense 2 to
4 inches thick and 2 to 4 inches wide southern pine lumber based on “other
technically sound criteria” as specified in Section 6.3.2.1 of P.S. 20. The decision
is also consistent with principles espoused in D-1990. For example, Section 7.1
of D-1990 dealing with extrapolation of values beyond a matrix sample
recognizes the reliance on “…additional supporting information to indicate that
the assigned values are conservative estimates.”
3. To clarify, in previous SPIB rules dense and non-dense classifications did not
apply to mixed southern pine, nor do the current approvals.
There being no further business, the meeting was adjourned.
Respectfully submitted,
Thomas D. Searles
Manager
Board of Review Minutes
March 9, 2012
Page 2
In granting the above approval the Board noted the following:
1. In the previous submission by SPIB, which was approved by the Board on
January 11, 2012, there was no differentiation between the design values for
No.2 Dense 2 to 4 inches thick and 2 to 4 inches wide and No. 2 Non-Dense 2 to
4 inches thick and 2 to 4 inches wide southern pine lumber.
2. There has been a historic recognition by the Board and by other respected
authorities that density of lumber contributes to its strength. The derivation of
the dense and non-dense values in the SPIB submission followed or improved on
procedures that have been used in previous submissions to the Board and in the
derivation of the original in-grade values. The new values are derived based
upon the latest test information and are not averages of past data. The Board
agrees with the SPIB statement that there was not enough data to assign design
values to all sizes and grades of southern pine lumber as originally proposed;
however, the Board also agrees that the use of the data from pieces actually
tested provides a conservative value for No. 2 Dense and No. 2 Non-Dense 2 to
4 inches thick and 2 to 4 inches wide southern pine lumber based on “other
technically sound criteria” as specified in Section 6.3.2.1 of P.S. 20. The decision
is also consistent with principles espoused in D-1990. For example, Section 7.1
of D-1990 dealing with extrapolation of values beyond a matrix sample
recognizes the reliance on “…additional supporting information to indicate that
the assigned values are conservative estimates.”
3. To clarify, in previous SPIB rules dense and non-dense classifications did not
apply to mixed southern pine, nor do the current approvals.
There being no further business, the meeting was adjourned.
Respectfully submitted,
Thomas D. Searles
Manager
SPIB submitted design values which proposed including all SYP dimensional (2x-4x) lumber in the derating although the test matrix was composed of only 2x4 material. At this time the derating only applies to what was tested, #2- 2x4's. ALSC's Board of Review has accepted the new proposed design values for #2 2x4's at this time. We really know nothing about the other dimensions but there is certainly cause to act conservatively.
From the Feb10.2012 report by SPIB to the BOR referenced above;
"Justification of #2 2x4 Dense and Nondense Southern Pine Design Values
Introduction
In the fall of 2011, SPIB submitted a proposal to the ALSC BOR to establish new design values
for dimension sizes of visual graded Southern Pine Lumber. These design values were based on
recent testing of #2 2x4 lumber. Because a significant reduction in properties was observed,
SPIB pursued a conservative route by logically apply these reductions and applicable parts of
ASTM D1990 to develop design values for wider widths and all NGR grades of visually graded
lumber. While the US Forest Products Lab agreed that the approach was appropriate while
additional testing is completed, the BOR opted to have the design values apply only to the size
and grade that was tested, and other 2x4 grades that are based solely on the #2 data collected.
This approach begs the question of how this applies to #2 Dense and #2 Nondense Southern Pine
2x4’s. Because the original submission was intended to apply to all widths and grades, SPIB
technical staff felt the extrapolation of the 2x4 data into dense and nondense subsets to be
applied to all grades and widths was too extreme. Since the BOR is limiting the application of
the 2x4 data to #2 and lower grades, the application of the dense and nondense data is the most
logical approach for maintaining dense and nondense #2 2x4 grades.
SPIB’s approach takes the recently collected data (2011) and sorts the lumber based on the
definition of density. Then nonparametric statistical analysis is done on these data subsets to
determine appropriate values for the dense and nondense lumber sorts. This submission
documents the definitions and procedures and how they are applied to the data, along with
conservative assumptions used for untested properties. The outcome is the most commonsensical
approach to publishing dense and nondense #2 2x4 design values."
From the Feb25 2012 letter to the BOR from FPL;
"Dear Tom:
In your letter of February 10th you requested that we review the submission from Southern Pine
Inspection Bureau (SPIB) titled "Justification for No.2 2x4 Dense and Non-dense Southern Pine Design
Values (an extension of the December 2011 submission)" which was dated February 2012 and the
accompanying excel data sheets. We have not had as much time as we would have liked to consider this
submission. We would typically expect to have a submission provided a minimum of one month in
advance, but we will provide you with our thoughts to this point. The approach used by SPIB to develop
design values for these grades is outside the procedures described in D1990. Fully representative samples
equal to or exceeding 360 pieces for Dense or Non-dense grade were not gathered. SPIB uses a Dense
and Non-dense sorting of the Unclassified grade sample (an approach that is similar and an improvement
on the approach used to derive the current design values published by SPIB and deemed acceptable by the
ALSC BOR in 1991) to derive their design values. The method used by SPIB to establish Dense and
Non-dense values are described as a "commonsensical approach" to publishing Dense and Non-dense
values for No. 2 grade 2 by 4 material. We will explain why the sorting and average "factor" approach
(the method used in 1991) was flawed and should not be perpetuated. We will report the reservations we
have with using the sorting method that SPIB did use in 2012 and indicate why we believe the design
values produced by SPIB for Dense and Non-dense No. 2 2 by 4 can, in all likelihood, be considered
conservative. We will leave it up to the judgment of the ALSC BOR as to whether this approach is a
common sense approach. Our more detailed response and comments are given below."
On another front, I think I posted when TP proposed another grading practice;
TPInspections proposed what NLGA (Canada's Nat'l Lumber Grading Authority, ~ their ALSC) calls a hybrid of the two existing practices that would allow mills to assign higher design values than those proposed by SPIB. This would require greater oversight, recordkeeping, and grading machines at the participating mills. This is under consideration but is really another matter. As NLGA correctly points out this should be proposed by a rules writing agency (SPIB) and would undergo scrutiny as a new method of determing design values. TPI's response was that they view this as a QC procedure rather than a rules change and that they are not proposing design value changes.
A little background,
ALSC oversees all the grading agencies through voluntary product standard DOC PS20. There will be a year after reference to PS20 to let you know which revision/timeframe you are looking at in this always evolving concensus standard.
SPIB is one of the seven "rules writing agencies" who write the grading rules for the species under their purview. TPInspections is probably the largest SYP grading agency, they are a non rules writing agency grading SYP under the SPIB rules. They are not limited to SYP, their west coast operations for example would grade dougfir under rule writing agency WWPA's rules for dougfir. There is self interest but this is more accurate and preserves higher values in more lumber. But, think about the smaller mill with output or a mix that cannot support this cost. I think there probably needs to be some form of shared misery among the participants to help incentivize climbing that hill and getting the entire industry moving in the right direction without sifting out producers by size. Lowering the cost of grading machines for this work is another path to investigate, I can do mechanical evaluation with a box of rocks.That field is wide open for R&D if we are moving toward some form of mechanical evaluation (I don't think in the long view that we are talking about one species). Presently ASTM's D-1990 provides the "standardized approach" for establishing design values.
This is from ALSC's Feb 1st meeting;
"The Board of Review at its meeting of January 5, 2012 reviewed a proposal from TP pertaining to an Audited Stress Rating program for visually graded lumber. The Board noted this was a unique program to be used at mills that visually grade dimension lumber so that higher stress values may be claimed based on enhanced sampling and testing of production to confirm that the claimed values are appropriate. The Board also noted that the proposal had not been tested in any mill to date. Many of those present at the Board meeting felt the proposal was an interesting concept and warranted further discussion by the ALSC. After a thorough deliberation, the Board referred the TP request to the Chairman of the ALSC for further consideration. ALSC Chairman Caron has asked that the Enforcement Subcommittee further consider the TP request. The Subcommittee will review the proposal as submitted by TP pertaining to an Audited Stress Rating program. The proposal is attached for ready reference."
From the Feb10.2012 report by SPIB to the BOR referenced above;
"Justification of #2 2x4 Dense and Nondense Southern Pine Design Values
Introduction
In the fall of 2011, SPIB submitted a proposal to the ALSC BOR to establish new design values
for dimension sizes of visual graded Southern Pine Lumber. These design values were based on
recent testing of #2 2x4 lumber. Because a significant reduction in properties was observed,
SPIB pursued a conservative route by logically apply these reductions and applicable parts of
ASTM D1990 to develop design values for wider widths and all NGR grades of visually graded
lumber. While the US Forest Products Lab agreed that the approach was appropriate while
additional testing is completed, the BOR opted to have the design values apply only to the size
and grade that was tested, and other 2x4 grades that are based solely on the #2 data collected.
This approach begs the question of how this applies to #2 Dense and #2 Nondense Southern Pine
2x4’s. Because the original submission was intended to apply to all widths and grades, SPIB
technical staff felt the extrapolation of the 2x4 data into dense and nondense subsets to be
applied to all grades and widths was too extreme. Since the BOR is limiting the application of
the 2x4 data to #2 and lower grades, the application of the dense and nondense data is the most
logical approach for maintaining dense and nondense #2 2x4 grades.
SPIB’s approach takes the recently collected data (2011) and sorts the lumber based on the
definition of density. Then nonparametric statistical analysis is done on these data subsets to
determine appropriate values for the dense and nondense lumber sorts. This submission
documents the definitions and procedures and how they are applied to the data, along with
conservative assumptions used for untested properties. The outcome is the most commonsensical
approach to publishing dense and nondense #2 2x4 design values."
From the Feb25 2012 letter to the BOR from FPL;
"Dear Tom:
In your letter of February 10th you requested that we review the submission from Southern Pine
Inspection Bureau (SPIB) titled "Justification for No.2 2x4 Dense and Non-dense Southern Pine Design
Values (an extension of the December 2011 submission)" which was dated February 2012 and the
accompanying excel data sheets. We have not had as much time as we would have liked to consider this
submission. We would typically expect to have a submission provided a minimum of one month in
advance, but we will provide you with our thoughts to this point. The approach used by SPIB to develop
design values for these grades is outside the procedures described in D1990. Fully representative samples
equal to or exceeding 360 pieces for Dense or Non-dense grade were not gathered. SPIB uses a Dense
and Non-dense sorting of the Unclassified grade sample (an approach that is similar and an improvement
on the approach used to derive the current design values published by SPIB and deemed acceptable by the
ALSC BOR in 1991) to derive their design values. The method used by SPIB to establish Dense and
Non-dense values are described as a "commonsensical approach" to publishing Dense and Non-dense
values for No. 2 grade 2 by 4 material. We will explain why the sorting and average "factor" approach
(the method used in 1991) was flawed and should not be perpetuated. We will report the reservations we
have with using the sorting method that SPIB did use in 2012 and indicate why we believe the design
values produced by SPIB for Dense and Non-dense No. 2 2 by 4 can, in all likelihood, be considered
conservative. We will leave it up to the judgment of the ALSC BOR as to whether this approach is a
common sense approach. Our more detailed response and comments are given below."
On another front, I think I posted when TP proposed another grading practice;
TPInspections proposed what NLGA (Canada's Nat'l Lumber Grading Authority, ~ their ALSC) calls a hybrid of the two existing practices that would allow mills to assign higher design values than those proposed by SPIB. This would require greater oversight, recordkeeping, and grading machines at the participating mills. This is under consideration but is really another matter. As NLGA correctly points out this should be proposed by a rules writing agency (SPIB) and would undergo scrutiny as a new method of determing design values. TPI's response was that they view this as a QC procedure rather than a rules change and that they are not proposing design value changes.
A little background,
ALSC oversees all the grading agencies through voluntary product standard DOC PS20. There will be a year after reference to PS20 to let you know which revision/timeframe you are looking at in this always evolving concensus standard.
SPIB is one of the seven "rules writing agencies" who write the grading rules for the species under their purview. TPInspections is probably the largest SYP grading agency, they are a non rules writing agency grading SYP under the SPIB rules. They are not limited to SYP, their west coast operations for example would grade dougfir under rule writing agency WWPA's rules for dougfir. There is self interest but this is more accurate and preserves higher values in more lumber. But, think about the smaller mill with output or a mix that cannot support this cost. I think there probably needs to be some form of shared misery among the participants to help incentivize climbing that hill and getting the entire industry moving in the right direction without sifting out producers by size. Lowering the cost of grading machines for this work is another path to investigate, I can do mechanical evaluation with a box of rocks.That field is wide open for R&D if we are moving toward some form of mechanical evaluation (I don't think in the long view that we are talking about one species). Presently ASTM's D-1990 provides the "standardized approach" for establishing design values.
This is from ALSC's Feb 1st meeting;
"The Board of Review at its meeting of January 5, 2012 reviewed a proposal from TP pertaining to an Audited Stress Rating program for visually graded lumber. The Board noted this was a unique program to be used at mills that visually grade dimension lumber so that higher stress values may be claimed based on enhanced sampling and testing of production to confirm that the claimed values are appropriate. The Board also noted that the proposal had not been tested in any mill to date. Many of those present at the Board meeting felt the proposal was an interesting concept and warranted further discussion by the ALSC. After a thorough deliberation, the Board referred the TP request to the Chairman of the ALSC for further consideration. ALSC Chairman Caron has asked that the Enforcement Subcommittee further consider the TP request. The Subcommittee will review the proposal as submitted by TP pertaining to an Audited Stress Rating program. The proposal is attached for ready reference."
AGENDA
BOARD OF REVIEW MEETING
April 18, 2012
I. ANTITRUST STATEMENT
II. MINUTES OF LAST MEETINGS
III. NeLMA RULES
NeLMA is re-publishing its rules with changes to include the various supplements that have already been approved and to include editorial changes to clarify certain portions of its rules.
IV. AGENCY AND LABORATORY ACCREDITATION OF PELLETS
1) Alberta Forest Products Association (AFPA) has applied to be accredited to provide supervisory and certification services to facilities that produce pellets under the ALSC Residential/Commercial Densified Fuel Policy (Wood Pellet Program). The Board will review the AFPA application.
2) The Canadian BioEnergy Centre, a division of the University of New Brunswick, has applied to be accredited to analyze densified fuel under the ALSC Residential/Commercial Densified Fuel Policy (Wood Pellet Program). The Board will review the Canadian BioEnergy Centre application.
V. TIMBER PRODUCTS INSPECTION (TP) REQUEST
TP has submitted an MSR Quality Control program. The Board will review this.
VI. CONTINUED REVIEW OF NLGA DESIGN VALUE DATA
The Board will continue its review of the NLGA design value data for SPF. The FPL will furnish its report regarding this matter.
VII. SAMPLING AND TESTING PLAN FOR DOUG FIR-LARCH AND
HEM-FIR
Report on the on-going Sampling and Testing plan for DF-L and Hem-Fir being conducted by PLIB, RIS, TP, WCLIB and WWPA. The Board will receive an update on the status of this plan.
Board of Review Agenda
April 18, 2012
Page 2
2
VIII. REPORT ON THE ON-GOING SPIB FULL MATRIX STATUS
The Board will receive an update on the status of this plan.
IX. SPF-S SAMPLING AND TESTING PLAN
The Board will receive an update on the status of the SPF-S sampling and testing plan being conducted by PLIB, RIS, TP, WCLIB, WWPA, NSLB, QFIC and NeLMA.
X. MACDONALD INSPECTION SERVICES (MI)
Macdonald Inspection (MI) has notified the Board of Review that it has terminated its services as of January 1, 2012 and that Canadian Softwood Inspection (CSI) will continue using its registered trade mark and will also continue the use of the MI mark which it now owns. CSI is providing services to the mills that were receiving service from MI.
XI. MISSISSIPPI STATE UNIVERSITY (MSU) INFORMATION
The Board of Review has received a program from MSU to examine within and between mill variations of southern pine lumber. The Board will review this request.
XII. REVIEW OF LUMBER AGENCY PERFORMANCE
XIII. REVIEW OF TREATED AGENCY PERFORMANCE
XIV. REVIEW OF WOOD PACKAGING MATERIAL AGENCY PERFORMANCE
XV. REVIEW OF PELLET PERFORMANCE
XVI. NEW BUSINESS
If anyone would like to attend the meeting, has any comments on any agenda item, or needs further information, please notify the ALS office.
BOARD OF REVIEW MEETING
April 18, 2012
I. ANTITRUST STATEMENT
II. MINUTES OF LAST MEETINGS
III. NeLMA RULES
NeLMA is re-publishing its rules with changes to include the various supplements that have already been approved and to include editorial changes to clarify certain portions of its rules.
IV. AGENCY AND LABORATORY ACCREDITATION OF PELLETS
1) Alberta Forest Products Association (AFPA) has applied to be accredited to provide supervisory and certification services to facilities that produce pellets under the ALSC Residential/Commercial Densified Fuel Policy (Wood Pellet Program). The Board will review the AFPA application.
2) The Canadian BioEnergy Centre, a division of the University of New Brunswick, has applied to be accredited to analyze densified fuel under the ALSC Residential/Commercial Densified Fuel Policy (Wood Pellet Program). The Board will review the Canadian BioEnergy Centre application.
V. TIMBER PRODUCTS INSPECTION (TP) REQUEST
TP has submitted an MSR Quality Control program. The Board will review this.
VI. CONTINUED REVIEW OF NLGA DESIGN VALUE DATA
The Board will continue its review of the NLGA design value data for SPF. The FPL will furnish its report regarding this matter.
VII. SAMPLING AND TESTING PLAN FOR DOUG FIR-LARCH AND
HEM-FIR
Report on the on-going Sampling and Testing plan for DF-L and Hem-Fir being conducted by PLIB, RIS, TP, WCLIB and WWPA. The Board will receive an update on the status of this plan.
Board of Review Agenda
April 18, 2012
Page 2
2
VIII. REPORT ON THE ON-GOING SPIB FULL MATRIX STATUS
The Board will receive an update on the status of this plan.
IX. SPF-S SAMPLING AND TESTING PLAN
The Board will receive an update on the status of the SPF-S sampling and testing plan being conducted by PLIB, RIS, TP, WCLIB, WWPA, NSLB, QFIC and NeLMA.
X. MACDONALD INSPECTION SERVICES (MI)
Macdonald Inspection (MI) has notified the Board of Review that it has terminated its services as of January 1, 2012 and that Canadian Softwood Inspection (CSI) will continue using its registered trade mark and will also continue the use of the MI mark which it now owns. CSI is providing services to the mills that were receiving service from MI.
XI. MISSISSIPPI STATE UNIVERSITY (MSU) INFORMATION
The Board of Review has received a program from MSU to examine within and between mill variations of southern pine lumber. The Board will review this request.
XII. REVIEW OF LUMBER AGENCY PERFORMANCE
XIII. REVIEW OF TREATED AGENCY PERFORMANCE
XIV. REVIEW OF WOOD PACKAGING MATERIAL AGENCY PERFORMANCE
XV. REVIEW OF PELLET PERFORMANCE
XVI. NEW BUSINESS
If anyone would like to attend the meeting, has any comments on any agenda item, or needs further information, please notify the ALS office.
From: "Tom Searles"
To: "ALSC - Tania Wagner"
Cc:
Date: Tue, 3 Apr 2012 12:42:07 -0400
Subject: FW: Southern Pine design value change - reaching out to registered design professional commnity
Tom - Frank Woeste and I taught a timber design course in Chicago a few weeks ago one topic we briefly discussed was the pending change in design values for Southern Pine lumber. The course had 52 engineers, and many of them had not heard anything about the issue. It became apparent to us that the “registered design professional” community may have been inadvertently left out of the “southern pine design values” news. Below listed are probably the two most prominent structural engineering magazines that have a web presence:
http://www.gostructural.com/
http://www.structuremag.org/
To appreciate the point, go to the sites and search the words “southern pine design values.” Nothing comes up related to changes that will take place two months.
This issue is important as registered design professionals (RDPs) are approving construction documents to be used for the rest of this year and the next in some cases. It is unlikely that a RDP that does a multitude of design work in concrete, steel, and to a lesser extent wood would see the SFPA, SPIB, SBCA, or other websites that have discussed the southern pine design values news. Please consider sending this note to all ALSC members and interested parties with the thought that it will give the group a chance to quickly inform the 10,000’s of structural engineers that use and approve southern pine.
Thanks,
...Don Bender
Consumer Representative
To: "ALSC - Tania Wagner"
Cc:
Date: Tue, 3 Apr 2012 12:42:07 -0400
Subject: FW: Southern Pine design value change - reaching out to registered design professional commnity
Tom - Frank Woeste and I taught a timber design course in Chicago a few weeks ago one topic we briefly discussed was the pending change in design values for Southern Pine lumber. The course had 52 engineers, and many of them had not heard anything about the issue. It became apparent to us that the “registered design professional” community may have been inadvertently left out of the “southern pine design values” news. Below listed are probably the two most prominent structural engineering magazines that have a web presence:
http://www.gostructural.com/
http://www.structuremag.org/
To appreciate the point, go to the sites and search the words “southern pine design values.” Nothing comes up related to changes that will take place two months.
This issue is important as registered design professionals (RDPs) are approving construction documents to be used for the rest of this year and the next in some cases. It is unlikely that a RDP that does a multitude of design work in concrete, steel, and to a lesser extent wood would see the SFPA, SPIB, SBCA, or other websites that have discussed the southern pine design values news. Please consider sending this note to all ALSC members and interested parties with the thought that it will give the group a chance to quickly inform the 10,000’s of structural engineers that use and approve southern pine.
Thanks,
...Don Bender
Consumer Representative
This came in yesterday from SBCCA and needs action from those interested by today. They appear to be requesting letters of support for a study. On the surface I agree with this page, I haven't read any deeper;
http://sbcmag.info/news/2012/apr/travis-seeking-support-msu-lumber-study
I think timing probably relates to;
There is an ALSC BOR meeting April 18th
http://sbcmag.info/news/2012/apr/travis-seeking-support-msu-lumber-study
I think timing probably relates to;
There is an ALSC BOR meeting April 18th
I didn't post the minutes of the April 18 BOR meeting. It was mostly legal manuevering by the various stakeholders which were answered and largely dismissed.
At this point the design reduction applies only to #2 2x4's this was a decision by the ALSC BOR, recommended effective date is Jun 1 2012. SPIB who operates under the ALSC then has the option of publishing new design values for #2 SYP 2x4's.
Here is SPIB's important notices page;
http://www.spib.org/important-notice.shtml
This is the publication of the new design values and effective date, 6/1/12, from SPIB (the grading rules writing organization for SYP)
http://www.spib.org/pdfs/Supplement-No-9-Tables-2002-sml-2x4-only.pdf
I'm not a legal beagle but the code references AF&PA's NDS, publication at awc.org;
http://awc.org/publications/update/designvaluechanges.html
click the right hand column links for ICC ammendment recommendations.
Not sure what Caeser is doing, in the field I hit close to the old design value limits on a floor a couple of weeks ago. I am trained as a grader, inspected the 2x12's, which at present are unaffected legally, to satisfy myself, it was a good load, most was actually #1. I felt confident the old values were good for that particular situation and those particular materials. On these larger dimensions, the critical spanning parts, I suspect we are some time out from a decision. If you read back you'll see I was suggesting using mixed SP values. In the field I was pushed to the line and you can see I cringed and used the old SYP values. I was lucky the load came in above grade, had it been pushing the line, I'm not sure what I could have or would have done. We are not in a good period right now, I can put my foot down and refuse to cross a line, that line is mighty nebulous in reality right now.
A little more background, as a result of in grade testing a decade or so ago there was readjustment of design values, narrower widths went up, wider went down. We are adjusting narrower widths down right now, I'm hoping the reductions in wider widths are less. We don't know that and the wood didn't change overnight.
That was a non answer, I'd like to hear how you all enforce things in the field as this evolves.
At this point the design reduction applies only to #2 2x4's this was a decision by the ALSC BOR, recommended effective date is Jun 1 2012. SPIB who operates under the ALSC then has the option of publishing new design values for #2 SYP 2x4's.
Here is SPIB's important notices page;
http://www.spib.org/important-notice.shtml
This is the publication of the new design values and effective date, 6/1/12, from SPIB (the grading rules writing organization for SYP)
http://www.spib.org/pdfs/Supplement-No-9-Tables-2002-sml-2x4-only.pdf
I'm not a legal beagle but the code references AF&PA's NDS, publication at awc.org;
http://awc.org/publications/update/designvaluechanges.html
click the right hand column links for ICC ammendment recommendations.
Not sure what Caeser is doing, in the field I hit close to the old design value limits on a floor a couple of weeks ago. I am trained as a grader, inspected the 2x12's, which at present are unaffected legally, to satisfy myself, it was a good load, most was actually #1. I felt confident the old values were good for that particular situation and those particular materials. On these larger dimensions, the critical spanning parts, I suspect we are some time out from a decision. If you read back you'll see I was suggesting using mixed SP values. In the field I was pushed to the line and you can see I cringed and used the old SYP values. I was lucky the load came in above grade, had it been pushing the line, I'm not sure what I could have or would have done. We are not in a good period right now, I can put my foot down and refuse to cross a line, that line is mighty nebulous in reality right now.
A little more background, as a result of in grade testing a decade or so ago there was readjustment of design values, narrower widths went up, wider went down. We are adjusting narrower widths down right now, I'm hoping the reductions in wider widths are less. We don't know that and the wood didn't change overnight.
That was a non answer, I'd like to hear how you all enforce things in the field as this evolves.
codeworks
REGISTERED
pc1, the formula is E = f/s or e=Pl/AE e= total deformation in inches, P= total force in pounds, l= length in inches, A = cross sectional area in square inches,E= modulu of elasticity in pounds per square inch, all from page 19 , simplified engineering for architects and builders, sixth edition, parker and ambrose, authors, a wiley publication