lkjh345
Structural
- Nov 16, 2005
- 416
I received the below email from AISC this afternoon. They are requesting help in working aginst a proposal by ASHRAE that they believe would favor concrete over steel in the design of 'green' building.
I have not yet studied the subject closely, but reprint the email here for everyone's consideration.
lkjh345
-----------------------------------------------------------
March 24, 2008
It is rare that the American Institute of Steel Construction contacts you by email to ask for your assistance. We are doing this today because of a matter that we believe is of critical importance to the structural steel industry, the design community and to the Code development process that embodies ANSI consensus procedures.
We have significant concerns with some developments in the recently published second draft of the proposed ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.) Standard 189.1 Standard for the Design of High-Performance Green Buildings Except Low-Rise Residential Buildings. Our concerns with this proposed standard are that we believe it:
is outside the scope and expertise for which ASHRAE is accredited
will result in adverse environmental impacts
includes provisions that we believe are unfair to steel, and inappropriately preferential to the interests of the concrete industry
adversely restricts the freedom of design professionals in their selection of structural framing materials
A more detailed discussion of these concerns follows the text of this email.
Please help us by becoming involved. Prior to April 7, 2008 you can submit your own comments on the proposed standard. Alternatively, we would be happy to add your name as a concurring party to the comments being submitted by AISC. In this case, we would need your reply to this email with your name and company affiliation no later than April 2, 2008.
We want to thank you for taking your time to consider this important matter.
Regards,
Dr. Louis Geschwindner, P.E.
Vice President - American Institute of Steel Construction
Mr. John Cross, P.E.
Vice President - American Institute of Steel Construction
---------------------------------------------------
The proposed ASHRAE standard, being developed jointly with the US Green Building Council (USGBC) and the Illuminating Engineering Society of North America (IESNA), is intended to provide minimum requirements of high-performance green buildings. Ultimately the goal of ASHRAE is to include 189.1 in the International Building Code as an appendix available for local adoption.
While addressing HVAC and lighting issues, the standard also establishes prescriptive requirements for construction materials, an area that we believe to be outside the scope and expertise of ASHRAE, USGBC and IESNA. In addition, the committee responsible for the proposed 189.1 standard was not constituted in a balanced manner under appropriate ANSI consensus protocol. We also believe that the committee lacks expertise in the area of construction materials, particularly as they relate to structural framing systems. The only individual on the committee with current, direct experience with construction materials is a paid staff member of CTL, Inc. which is a subsidiary organization of the Portland Cement Association.
This apparent lack of balance and expertise has resulted in provisions that AISC believes to be significantly slanted toward the interests of the cement and concrete industry. For example, section 9.4.1.1 reads:
9.4.1.1 Recycled Content. The sum of post-consumer recycled content plus one-half of the pre-consumer recycled content shall constitute a minimum of 10%, based on cost, of the total materials in the building project. The recycled content value of a material assembly shall be determined by weight. The recycled fraction of the assembly shall then be multiplied by the cost of the assembly to determine recycled content value. Not more than 5% (one-half of the 10%) of the recycled content for this requirement shall come from one type of material such as steel or concrete.
The annual average industry values for the recycled content of steel products manufactured in basic oxygen furnaces and electric arc furnaces are allowed to be used as the recycled content of steel. The recycled content of the supplementary cementitious material (e.g. fly ash, slag cement, or silica fume) in concrete is allowed to be used as the recycled content of the concrete when the total amount of cementitious materials in the actual mix design is not increased compared to a baseline 28-day strength mix design using only Portland cement and complying with the same performance requirements.
The effect of this section will be to arbitrarily reduce the recycled content contribution of structural steel by over 50% while inappropriately increasing the contribution credited to concrete by over 700%. To our knowledge no scientific or engineering justification has been provided to support this assignment of recycled content credit. Application of this standard as part of the building code could significantly impact your freedom to exercise your independent engineering judgment when selecting structural framing materials for individual construction projects.
Contrary to the proposed standard, design professionals who work with both steel and concrete know that the recycled content of cement is not the same as the recycled content of concrete. There is a big difference between cement and concrete!
It is our belief that any standard that impacts the selection of structural framing materials should be developed on a consensus basis with knowledgeable representatives of all involved parties - applicable trade associations, structural engineers, architects, as well as material producers, suppliers, contractors and fabricators.
There were many aspects of the first draft of 189.1 that AISC commented on in the first round of comments. Regretfully, our comments appear to have been largely ignored without comment in the publication of the second draft. We will again be submitting numerous comments to the committee prior to the April 7, 2008 deadline.
What can you do?
We would ask you to become involved in one of two ways.
We encourage you as a design professional to submit your own comments on the proposed 189.1 standard reflecting your own thoughts on section 9.4.1.1 as well as on the remainder of the document. You can obtain a copy of draft 2 of the proposed ASHRAE 189.1 standard from the ASHRAE website, You will find a zip file containing the 189.1 draft, a comment form and instructions located under the "45 Day Public Review Drafts" Section. Comments must be submitted by April 7, 2008.
If you choose not to submit your own comments, we would ask you to allow us to add your name as a concurring party to the three comments being submitted by AISC. These three comments deal with:
Section 9 of the proposed standard being outside the scope and expertise of ASHRAE and reflective of a non-consensus process of an unbalanced committee
The arbitrary limitation of the recycled content contribution of any material (in reality it only impacts structural steel) to 5%
The special treatment provided to the cement and concrete industries to utilize the recycled content value of cement for the recycled content of the entire mass and volume of the concrete without apparent scientific or engineering support for that provision
Draft copies of our comments can be found at
We would encourage you to record your agreement with these comments by replying to this email with your name and company affiliation no later than April 2, 2008.
I have not yet studied the subject closely, but reprint the email here for everyone's consideration.
lkjh345
-----------------------------------------------------------
March 24, 2008
It is rare that the American Institute of Steel Construction contacts you by email to ask for your assistance. We are doing this today because of a matter that we believe is of critical importance to the structural steel industry, the design community and to the Code development process that embodies ANSI consensus procedures.
We have significant concerns with some developments in the recently published second draft of the proposed ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.) Standard 189.1 Standard for the Design of High-Performance Green Buildings Except Low-Rise Residential Buildings. Our concerns with this proposed standard are that we believe it:
is outside the scope and expertise for which ASHRAE is accredited
will result in adverse environmental impacts
includes provisions that we believe are unfair to steel, and inappropriately preferential to the interests of the concrete industry
adversely restricts the freedom of design professionals in their selection of structural framing materials
A more detailed discussion of these concerns follows the text of this email.
Please help us by becoming involved. Prior to April 7, 2008 you can submit your own comments on the proposed standard. Alternatively, we would be happy to add your name as a concurring party to the comments being submitted by AISC. In this case, we would need your reply to this email with your name and company affiliation no later than April 2, 2008.
We want to thank you for taking your time to consider this important matter.
Regards,
Dr. Louis Geschwindner, P.E.
Vice President - American Institute of Steel Construction
Mr. John Cross, P.E.
Vice President - American Institute of Steel Construction
---------------------------------------------------
The proposed ASHRAE standard, being developed jointly with the US Green Building Council (USGBC) and the Illuminating Engineering Society of North America (IESNA), is intended to provide minimum requirements of high-performance green buildings. Ultimately the goal of ASHRAE is to include 189.1 in the International Building Code as an appendix available for local adoption.
While addressing HVAC and lighting issues, the standard also establishes prescriptive requirements for construction materials, an area that we believe to be outside the scope and expertise of ASHRAE, USGBC and IESNA. In addition, the committee responsible for the proposed 189.1 standard was not constituted in a balanced manner under appropriate ANSI consensus protocol. We also believe that the committee lacks expertise in the area of construction materials, particularly as they relate to structural framing systems. The only individual on the committee with current, direct experience with construction materials is a paid staff member of CTL, Inc. which is a subsidiary organization of the Portland Cement Association.
This apparent lack of balance and expertise has resulted in provisions that AISC believes to be significantly slanted toward the interests of the cement and concrete industry. For example, section 9.4.1.1 reads:
9.4.1.1 Recycled Content. The sum of post-consumer recycled content plus one-half of the pre-consumer recycled content shall constitute a minimum of 10%, based on cost, of the total materials in the building project. The recycled content value of a material assembly shall be determined by weight. The recycled fraction of the assembly shall then be multiplied by the cost of the assembly to determine recycled content value. Not more than 5% (one-half of the 10%) of the recycled content for this requirement shall come from one type of material such as steel or concrete.
The annual average industry values for the recycled content of steel products manufactured in basic oxygen furnaces and electric arc furnaces are allowed to be used as the recycled content of steel. The recycled content of the supplementary cementitious material (e.g. fly ash, slag cement, or silica fume) in concrete is allowed to be used as the recycled content of the concrete when the total amount of cementitious materials in the actual mix design is not increased compared to a baseline 28-day strength mix design using only Portland cement and complying with the same performance requirements.
The effect of this section will be to arbitrarily reduce the recycled content contribution of structural steel by over 50% while inappropriately increasing the contribution credited to concrete by over 700%. To our knowledge no scientific or engineering justification has been provided to support this assignment of recycled content credit. Application of this standard as part of the building code could significantly impact your freedom to exercise your independent engineering judgment when selecting structural framing materials for individual construction projects.
Contrary to the proposed standard, design professionals who work with both steel and concrete know that the recycled content of cement is not the same as the recycled content of concrete. There is a big difference between cement and concrete!
It is our belief that any standard that impacts the selection of structural framing materials should be developed on a consensus basis with knowledgeable representatives of all involved parties - applicable trade associations, structural engineers, architects, as well as material producers, suppliers, contractors and fabricators.
There were many aspects of the first draft of 189.1 that AISC commented on in the first round of comments. Regretfully, our comments appear to have been largely ignored without comment in the publication of the second draft. We will again be submitting numerous comments to the committee prior to the April 7, 2008 deadline.
What can you do?
We would ask you to become involved in one of two ways.
We encourage you as a design professional to submit your own comments on the proposed 189.1 standard reflecting your own thoughts on section 9.4.1.1 as well as on the remainder of the document. You can obtain a copy of draft 2 of the proposed ASHRAE 189.1 standard from the ASHRAE website, You will find a zip file containing the 189.1 draft, a comment form and instructions located under the "45 Day Public Review Drafts" Section. Comments must be submitted by April 7, 2008.
If you choose not to submit your own comments, we would ask you to allow us to add your name as a concurring party to the three comments being submitted by AISC. These three comments deal with:
Section 9 of the proposed standard being outside the scope and expertise of ASHRAE and reflective of a non-consensus process of an unbalanced committee
The arbitrary limitation of the recycled content contribution of any material (in reality it only impacts structural steel) to 5%
The special treatment provided to the cement and concrete industries to utilize the recycled content value of cement for the recycled content of the entire mass and volume of the concrete without apparent scientific or engineering support for that provision
Draft copies of our comments can be found at
We would encourage you to record your agreement with these comments by replying to this email with your name and company affiliation no later than April 2, 2008.
