Ongoing Proposal Support Documentation
ICC 2025 Group B
Infill Spread Proposals

IBC-S Proposal S80-25 & IRC-B Proposal RB53-25

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Basis of Webpage Information:

The information on this webpage will be getting updated periodically as more information is documented throughout the life span of the ICC’s 2025 Group B code cycle.  The intent is to allow additional information to be accessed openly throughout the code cycle as new information is brought to lite and to provide responses to questions that arise during CAH-1 and CAH-2 hearings, workgroup meetings, including possible comments and the ICC Group B public comment hearings for this model code cycle.

The information is a more detailed summary account of an array of information and testing research done to correlate a pound-force load on a sphere in relation to ASTM E935-00 “Test Method D – Application of horizontal static load to determine resistance to cone penetration by infill area of picket and panel railing systems”, and first published by ASTM in the designation: E 935 – 91 “Standard Test Methods for Performance of Permanent Metal Railing Systems and Rails for Buildings1“, and then include this corelated cone load to a sphere load as a proposal for a infill spread load for the model 2027 IBC & 2027 IRC.

For those of you who are not familiar with this “Test Method” it was reviewed and developed by the same group who also published the method for testing the 1sqft area load test, published in the same ASTM E935-91 standard as “Test Method C” at the same time, and has been continued to be published in one form or another, in every published model IBC since 2000, to the current 2024 in section “1607.9.1.2 Guard component loads”, and and first published in the 2001 IRC Supplement in table R301.5.

Working Group Zoom Meetings

The proponent is inviting interested parties to join ongoing periodic zoom meetings to discuss the information and the proposals.  The workgroup meetings will begin in March of 2025 and run through Spring of 2026 till the ICC’s Public Comment Hearings.

Interested parties can signup for email notifications on the top right of this webpage to receive emails when this website is updated with new documentation and information, and to join the invitation list for workgroup meetings.

Currently we are planning the first workgroup meeting for 1:00pm Tuesday March 18th, 2025.

BRIEF HISTORY of the ESTABLISHMENT of the ASTM E935 STANDARD

ESTABLISHMENT of the ASTM E935 Standard

  • The initial publication of ASTM E935 in 1983 included 2 test methods,
    • “Test Method A – Horizontal Static Load Application” and
    • “Test Method B – Vertical Static Load Application”.

  • ASTM E935-83 Initial Standard Publication
    • The initial publication of ASTM E935 in 1983 included 2 test methods,
      • “Test Method A – Horizontal Static Load Application” and
      • “Test Method B – Vertical Static Load Application”.
  • ASTM E935-91 Standard Expands from 2 Test Methods to 4 Test Methods
    • To begin the updated standard made changes to the titles for the first 2 Test Methods A and B.
      • The new titles provided clarity that they applied to the “Top Rail”, and not the lower infill area.
        • Test Method A was renamed “Application of Horizontal Static Load to Top Rail”, and
        • Test Method B was renamed “Application of Vertical Static Load to Top Rail”,
    • The two new test methods added to the updated 1991 standard focused specifically on the Infill.
      • The first of the 2 new test methods added was
        • “Test Method C – Application of Horizontal Static Load to Infill Areas of Picket and Panel Railing Systems”,
        • Test Method C is the current 1-sqft area load
      • The second of the 2 new test methods added was
        • “Test Method D – Application of Horizontal Static Load to Determine Resistance to Cone Penetration by Infill Area of Baluster and Panel Railing Systems.”,
        • Test Method D was specifically developed as a counter part to Test Method C to be able to test the spread between infill elements in guard systems.
    • ASTM E935-91 cites ASTM E985 “Specifications for Permanent Metal Railing Systems and Rails for Buildings” for the specific loads to be used for each of the 4 test methods in ASTM E935.

  • The 2000 edition of the last updated edition of ASTM E935 which included the test method for guard infill deflection as;
    • “Test Method D – Application of Horizontal Static Load to Determine Resistance to Cone Penetration by Infill Area of Baluster and Panel Railing Systems”.
  • E935-00 cites, as did the 1991 test method, to use
    • E985-00 for the load that will be applied for Test Method D, and
    • Specifically in section 7.1.8 “The minimum horizontal test load to be applied by a penetration cone to the infill area of a baluster or panel railing system (see Test Method D of Test Methods E935) shall be 220 N (50 lbf).”
  • Specifics of importance in ASTM E935-00, in Test Method D
    • Test Method D specifies when testing to use a cone that is 1.25% the size of the opening limitation.
      • This translates to using a 5-inch Cone for testing an opening limitation of 4-inches in guard infill.
    • The test method specifies that the cone’s point be truncated to 1-inch in diameter.
      • For this reason we have limited the load requirement in this proposal to openings that allow a sphere 1.25-inches in diameter to pass through.
      • Openings smaller than the 1.25-inch sphere are exempt from this requirement

  • The current edition of ASTM E935-21 does not include “Test Method D”.
  • E935 was re-written to be more inline with only the sections of the “code” which were being used and removed sections that were never adopted and published as E935-13.
    • The revisions in E935-13 of the Test Method Document outlined the test methods in Section 10 Procedure.
  • Though some may argue that a lack of adoption means that “Test Method D” is not valid,
    • We believe and present the fact that 3 of the 4 test methods first developed over 40 and 30 years ago in the History of E935 are still used and that it took simply 30 years to add the 4th test method to clarify minimum compliance for infill spreading only when the building code industry saw the need for the code to finely clarify this detail at this time.

Identifying Openings in Guard Infill most Vulnerable to Spreading through Penetration

To simplify the code submittal which will apply to guard infill, the proposal focused on wire cables as they are the most vulnerable and scrutinized type of guard infill for opening spreading/deflection concerns.  Furthermore, we narrowed the monograph reason statement even further to focus on the most vulnerable common wire cable used in the built environment,

  • Imported 1/8-inch diameter 1×19 type 316 stainless steel, arguably the most flexible type of infill commonly used in guard systems

With the 2 proposals submitted in the IBC-S and IRC-B adding the requirement to all types of guard infill.  We have been questioned on how does this affect other types of guard infill.   We will be covering and testing different types of guard infill configurations, materials and construction on this website over time, and then post summaries of that information once completed.

However, as noted the research started with the results of the most vulnerable.  For the purposes of this research for the code change proposals we believe  that wire cable guard infill, being the most scrutinized by code officials during inspections is likely the most affected by the addition of the newly proposed model code requirements.

Safe Cable Design Loads

The tensioning, stiffness and resistance that a guard’s infill performs to is directly related to the construction and materials, and with wire cable this is directly related to safe cable design loads.  Per industry manufacture Loos & Co. Inc., 1/8-inch diameter, 1×19 type 316 stainless steel imported wire cable, lists the minimum break point at 1,780lbf on their website (01/07/2025).

For this study we started from a base zero knowledge of how much tension will be needed to meet the 50lbf designated.  We applied the cable’s designated minimum break load of 1,780lbf to the industry-based safety factors to determine the maximum Safe Workload and the maximum Pretension load for the cable.

  • The workload limit is the maximum tension that each cable can be set at for static, for the installation.
    • The safe workload limit is based on 20% of the cable’s minimum break load, this translates to 356lbf for our study
  • The pretension load is the suggested maximum cable pretension pound-force for installation.  This is done to remove the stretch and slack from a cable up front and then reduced back to the workload designated for the projects installation.
    • The pretension load limit is based on 25% of the cable’s minimum break load, which translates to 445lbf for our study

For the setup of this projects first phase review each of the cables in the guards frame where first pre-tensioned to approximately 330lbf and held for 3 minutes and then reduced back to approximately 100lbf of tensioned, one at a time.  Once each of the cables went through the pretension process, the cables were then tensioned up in rotation to a starting load of 220lbf, tightening from the center cable out in 20lbf increments till all cable showed just 220lbf.

The cone was pulled through to fail to record the pound-force load needed 3 times, then the cables were tightened increasing the tension by 10lbf each time till we observed a pound-force load close to the cones pull through target of 53lbf.  The target pound-force of 53lbf was set by adding the designated ASTM E985-00 50lbf, with the average pull to move pound-force registering as the drag to move the 64lb steel cone on the testing rig.

Context Pictures of Testing Configurations

First Stage Process Videos

The (2) videos below in this section are a simplified explanation of the method followed in determining the load used in the proposals submitted.  The wire infill cables were tensioned uniformly, (Between 246 & 247 lbf), until the infill met enough tension for the 50lbf, designated in E985-00, was seen and recorded on the cone’s load cell sensor.  The video shows the pound-force was over the 50lbf , however we needed to account for the drag load being seen and recorded to get and keep the cone moving before contacting the infill cables.  This is why the start point is set with the face of the cone & sphere vertically inline with the infill.

Once the guard’s infill section met the Part D Test Method of E935-00 after a consistent minimum of 5 consecutive test, we changed out the 5-inch cone, 1.25% of the sphere opening, designated in ASTM E935-00 with the 4-inch sphere apparatus.  The 4-inch sphere apparatus was then pulled while viewing and logging the tension through to failure recording the results, repeating the test pulls multiple times.

The results produced data which was reviewed to determine and establish the proposed pound-force load to be applied to the sphere for the requirements listed in the code change proposals.

First Phase Clear Span 5-in Cone Test

First Phase Clear Span 4-in Sphere Test