# Design Values for Joists and Rafters - Visually Graded Mixed Southern No. 2



## GBrackins (Mar 30, 2012)

Received this from the American Wood Council today ...

The American Lumber Standard Committee (ALSC) Board of Review has approved changes to design values for 2"- 4" thick, 2"- 4" wide, Southern Pine #2 Dense and 2x4 Mixed Southern Pine #2 and all lower grades (i.e. #3, Stud, Construction, Standard, and Utility) with a recommended effective date of June 1, 2012, to allow for their orderly implementation.

In advance of the implementation date, AWC has developed an addendum to the Design Values for Joists and Rafters [http://www.awc.org/publications/update/2012DVJR-Addendum-March2012.pdf] that provides design values for these sizes and grades of Southern Pine and Mixed Southern Pine to use with the Span Tables for Joists and Rafters.

Since you recently downloaded a copy of the 2012 Design Values for Joists and Rafters from the AWC website, you are encouraged to download the addendum from the link given above.

Hope this information helps.

Technical Inquiry Clearinghouse

American Wood Council

803 Sycolin Road, Suite 201

Leesburg, VA 20175

info@awc.org

202-463-4713

www.awc.org

newAWClogofinaltextrightcaps-small

http://www.awc.org/publications/update/2012DVJR-Addendum-March2012.pdf


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## Mark K (Mar 30, 2012)

Unless you amend your local building code these new values cannot be required by the building department.


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## GBrackins (Mar 30, 2012)

but if you are a builder designer does the change in values come into play?


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## Mark K (Mar 30, 2012)

As an applicant you can and probably should use these new values in your design as long as they produce a more conservative design than the code sanctioned values would require.


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## DRP (Mar 31, 2012)

Bear in mind that the SPIB requested a reduction in design values across the table. They are awaiting further testing results before broadening the change. Conservative might be applying reduced values to those sizes and grades that were unaffected by derating in this round... which effectively gives no advantage to specifying SYP. It doesn't matter what the codebook says if you know better.


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## ICE (Mar 31, 2012)

Tessimm said:
			
		

> Oh, that's Great SIR !!


What's with the inane replies.  It's not spam and the same reply will show up at several threads.  Most of them sound like English is a third language. So what's it all about?


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## DRP (Mar 31, 2012)

It's a spam placeholder, check the IP and it'll be from abroad. They make a post that an inattentive moderator lets slide by, then they come back later and edit to place ads/whatever. In this case they will need to pony up to get an edit button  

I'm all for peace, love, and free speech too, just remember, those folks don't believe that drivel. Throw them out the door.


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## GBrackins (Apr 14, 2012)

Here is a link so you can download "Supplement No. 9 to the Southern Pine Inspection Bureau 2002 Grading Rules." This goes into affect June 1, 2012. This will provide changes to the design values as listed in Tables 1.A, 3, 6 & 7.

http://www.spib.org/pdfs/Supplement-No-9-Tables-2002-sml-2x4-only.pdf


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## GBrackins (Apr 14, 2012)

Here is a link so you can download an addendum from the American Wood Council for the 2012 National Design Specification for Wood Construction Manual.

http://www.awc.org/publications/update/2012NDS-Addendum-March2012.pdf


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## fatboy (Apr 15, 2012)

Sorry I missed the "spam", gone now. I delete when I see them. Not really spam, but serves no purpose in my opinion. Let me know when you see them.


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## gbhammer (Apr 16, 2012)

Awhhh the spam are funny.


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## GBrackins (May 25, 2012)

Received this from the SBCA today, Since it appears that in the short term the International Code Council (ICC) is taking essentially a “hands off” position with respect to implementation of SP design value changes, and leaving it to others to decide their best course of action, SBCA recommends that all component manufacturers consider customizing and sending out SBCA’s template letter (which can be downloaded by clicking the .doc link below) to all customers, potential customer, specifiers and building officials, disseminating it through every communication channel you can.

http://sbcmag.info/sites/sbcmag.info/files/ind_news/2012/05/120524_sp_design_value_template_letter_final_doc_14168.doc

May 24, 2012

Name

Address

City, State Zip

Dear :

RE: Implementing the Southern Pine (SP) design value changes effective June 1, for both prescriptive and engineered applications of lumber.

In the absence of clear direction from a variety of sources surrounding the enforcement of lumber design value changes, our company, in concert with our trade association, the Structural Building Components Association (SBCA),  has realized that all prescriptive and engineered applications of  lumber must, as of June 1, 2012, utilize the design values published in the Southern Pine Inspection Bureau’s (SPIB) Supplement No. 9 to the 2002 Standard Grading Rules for Southern Pine Lumber that become effective June 1, 2012.

We have made this determination based on the following observations:

•	The building code (prescriptive and engineered), along with all structural engineering, is founded on principles intended to establish provisions consistent with the scope of the code and generally accepted engineering practice that adequately protects public health, safety and welfare.

•	For construction purposes, lumber grade-marks = lumber design values.

•	It is appropriate to use the lumber expertise and judgments made by the American Wood Council (AWC), and follow AWC’s lead by using the post-June 1, 2012 design values for all Southern Pine (SP) lumber-related structural resistance by June 1, as applied in their Maximum Span Calculator for Wood Joists & Rafters : (http://www.awc.org/calculators/span/calc/timbercalcstyle.asp) .

•	Adopting the AWC position and June 1, 2012 implementation approach is consistent with the recommendations of the ALSC, the SPIB Supplement No. 9 and the ICC’s reference to ALSC’s cautionary language stating, “[ALSC] cautions all interested parties to take note of all available information in making design decisions in the interim.” The values in the SPIB proposal represent approximately a 25-30% reduction. Many of the critics of the proposal acknowledged that some reductions were in order, albeit the magnitude of those reductions was disputed. All design professionals are advised in the strongest terms by the Board to evaluate this information in formulating their designs in the interim period.”

SPIB’s Supplement No. 9 sets out the new design values effective June 1, 2012. Consistent with the ALSC Ruling, the only design values that will change on June 1, 2012 apply to visually graded Southern Pine and Mixed Southern Pine sized 2” to 4” wide and 2” to 4” thick (2x2s through 4x4s) in No.2 and lower grades (No.2DNS, No. 2, No. 2NonDNS, No.3, Stud, Construction, Standard and Utility).

Given the ALSC Board’s ruling, and SPIB’s publishing of Supplement No. 9 to the 2002 Standard Grading Rules for Southern Pine Lumber, all prescriptive framing and component designs completed after June 1, 2012 should be implemented in accordance with the design values contained in Supplement No. 9, unless the residential or commercial designs using “pre-June 1, 2012 Design Values” are approved by the project Owner/Building Designer/Engineer of Record before June 1, 2012.

We believe this approach is consistent with the intent of the ALSC Board’s ruling and SPIB’s Supplement No. 9 effective date of June 1, 2012.  We would be more than happy to discuss our stated approach in greater detail and answer any questions you may have.

Sincerely,


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## GBrackins (Jun 14, 2012)

For those that might have missed the Woodworks.org webinar (that was posted under Training Section) here is a link to the slideshow for their presentation. Enjoy!

http://woodworks.org/wp-content/uploads/SFPA-Design-Values.pdf


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