Volume 9, Issue 3 - March 2008
The VOTES are In
In early February, code officials from across the United States gathered in Palm Springs, Calif., for two weeks to review the hundreds of proposals for code changes that were brought before them. DWM monitored the hearings of the International Code Council (ICC) and has compiled those that are relevant for door and window manufacturers here—covering everything from deflection to solar heat gain coefficients (SHGCs).
Part two of E37, as proposed by Julie Ruth of JRuth Code Consulting, representing the American Arch-itectural Manufacturers Association (AAMA), suggested striking language from R311.2 requiring dwelling egress doors to be “not less than 3 feet in width,” replacing this language with a requirement that these doors “shall provide a minimum clear width of 32 inches when measured between the face of the door and the stop, with the door open 90 degrees.”
Ruth maintained that the current language failed to address the actual opening size and language should be modified to clarify.
“We started out looking at the IRC,” Ruth explained. “The IRC, for a long time, has said the egress door has to be a minimum width of 36 inches. There’s some confusion as to what is actually supposed to be 36 inches—the door slab, the opening and so on,” she said. “So we started looking at trying to correct that and examined the language in the IBC. And the language in the IBC deals with the actual opening, the part people actually pass through. We wanted to try and take that language put it into the IRC. But we looked at that language and felt there was also an opportunity to improve some of that language.”
E37 would have adjusted language calling for a minimum clear height of the door opening to not be less than 78 inches, measured from the top of the threshold to the bottom of the stop, opposed to previous language stating an 80-inch minimum.
Several opponents of the change suggested that a minimum height opening of 78 inches could present problems for taller individuals. Other said that an actual opening size of 78 inches might require a slab size greater than was currently allowed by the 80-inch requirement. A modification was suggested to maintain language requiring a minimum height opening of 80 inches and E37 was approved with the suggested modification.
ICC Strikes Section Limiting Trade-offs
“402.6 Maximum fenestration U-factor and SHGC. (Mandatory). The area weighted average maximum fenestration U-factor permitted using trade-offs from Section 402.1.4 or Section 404 shall be 0.48 in zones 4 and 5 and 0.40 in zones 6 through 8 for vertical fenestration, and 0.75 in zones 4 through 8 for skylights. The area weighted average maximum fenestration SHGC permitted using trade-offs from Section 404 in Zones 1 through 3 shall be 0.50.”
Proponents of the change included Lawrence Brown of the National Association of Home Builders (NAHB). Brown maintained that limits on fenestration U-factor and SHGC trade-offs restricted ways by which code compliance can be achieved. He suggested that by definition trade-offs are energy-neutral and do not save energy, making section 402.6 unnecessary.
“This deletes a section that neither saves or uses energy,” Brown said.
Deflection Limits for Aluminum Used in Skylights and Sunrooms are
The proposal was approved by a vote of 13-0.
Footnote “h” of Table 1604.3 will now read: “For aluminum structural members or aluminum panels used in skylights and sloped glazing framing, roofs or walls of sunroom additions or patio covers, not supporting edge of glass or aluminum sandwich panels, the total load deflection shall not exceed L/60. For continuous aluminum structural members supporting edge of glass, the total load deflection shall not exceed L/175 for each glass lite or L/60 for the entire length of the member, whichever is more stringent. For aluminum sandwich panels used in roofs or walls of sunroom additions or patio covers, the total load deflection shall not exceed L/120.”
Footnote “c” of Table R301.7 will now read: “For aluminum structural members or panels used in roofs or walls of sunroom covers, not supporting edge of glass or sandwich panels, the total load deflection additions or patio shall not exceed L/60. For continuous aluminum structural members supporting edge of glass, the total load deflection shall not exceed L/175 for each glass lite or L/60 for the entire length of the member, whichever is more stringent. For sandwich panels used in roofs or walls of sunroom additions or patio covers, the total load deflection shall not exceed L/120.”
Mike Fischer, code consultant for the Window and Door Manufacturers Association (WDMA) and an original author of the footnote, spoke in favor of the addition.
“We didn’t tell the code officials [in the original footnote] what the deflection limit should be,” he said. “This language is much better worded.”
He added, “For this application, it needs to be L/175.”The vote was 13-0.
Overhangs are now a Trade-off for SGHCs
“We believe that if a shading device is part of an architectural structure that credit should be given,” said proponent Lovell, representing the Association of Industrial Metallized Coaters and Laminators.
Lovell referred to this change as mainly editorial. However, others in attendance argued that it was more than that.
Garrett Stone of Cardinal Glass Industries brought up several concerns—including the difficulty in enforcing the code, the complexity of calculating the projection factor and the fact that overhangs cost more than energy-efficient windows. He also brought up the issue of high-impact areas.
“The other problem that I wonder about is impact glazing. This is basically a prescription to put wings on buildings,” he said. “Let’s put a big wing on it and protect it from having to install energy-efficient windows.”
Fischer argued that Lovell makes a valid point, but this shouldn’t be added to the code.
“Are these things worth consideration?” Fischer asked. “Of course. Do they belong in a prescriptive code? Not in this form.”
Fischer added that due to the movement of the sun, the projection factor would change throughout the day.
“The overhang only covers the window 100 percent when it’s noon,” he said.
Lovell stressed that this would only be an option, not a requirement.
Darrell Smith of the International Window Film Association also spoke out—noting that several glass manufacturers were against the modification, as it would allow consumers to utilize clear glass in their windows with overhangs.“If I elect to have an overhang that effectively blocks all the solar energy that I want it to, why shouldn’t I be allowed to have clear glass?” he asked.
“If we don’t bring these standards forward and advocate for quality products meeting the latest standards, state officials will do it for us,” said Fischer, speaking on behalf of WDMA.
The Association of Millwork Distributors’ (AMD) director of codes and standards Jeff Burton spoke against the code amendment. He also provided scientific evidence from three sources that exterior side-hinged doors proved no significant failures or water infiltration problems during the recent hurricane seasons.
AMD president Larry Ray representing pre-hanger GHDC Inc. in Tupelo, Miss., also spoke against the proposed amendment and discussed the economic problems that S141 could cause if implemented. There was some concern that the proposed standard tends to favor providers of complete door systems that have resources to develop, test and provide an integrated system. If passed this would have put pre-hangers that typically source their components from multiple suppliers at a disadvantage.
The IRC committee voted unanimously 9-0 not to approve the proposed standard.
Proposal to Make AAMA 507 an Alternative to NFRC Rating Defeated
Subsequently, the group—of which Craig Conner with Building Quality, Ruth (representing AAMA) and Rand Baldwin for the Aluminum Extruders Council (AEC) also are part—proposed the addition of the following subsections, 188.8.131.52 Fenestration rating by NFRC 100 and NFRC 200, 184.108.40.206 Commercial fenestration alternative rating by AAMA 507 and 220.127.116.11 Default values for fenestration rating.
They proposed the addition of curtainwall and storefront glazing to the definition of fenestration as used in Section 202’s general definitions and would like to see the addition of an AAMA standard (507-07, “Standard Practice for Determining the Thermal Performance Characteristics of Fenestration Systems Installed in Commercial Buildings”) to Chapter 6.
Connor provided the first written reason for the group’s proposal: “The reason for this change is simple. Commercial windows should be rated for energy efficiency.”
Ruth added that “[this] proposal would permit the use of AAMA 507 to determine the U-factor and SHGC of glazed assemblies in commercial buildings …”The proposal was defeated 10-4 after two modifications to it were approved.
Proposal to Move IECC into IRC Defeated
Opponents to this proposal came out in full force. Among them was Fischer.
“I want to point out that there’s a myth that we have to have a single, stand-alone code,” he told the committee. “We don’t.”
Culp, rebutted, saying, “Again, we’re not eliminating the IECC—the IECC will still have residential provisions so those programs can continue as is.”
The committee voted the proposal down 6-5.
Proposal Regarding U-Factor Changes for Climate Zones 6 and 7
Connor proposed the same changes be made to the corresponding tables in the IRC, Table N1102.1 (Insulating and Fenestration Requirements by Component) and Table N1102.1.2 (Equivalent U-Factors. For Tables 402.1.1 and N1102.1). Connor also proposed a footnote that the SHGC factor would be the value tested by the NFRC.
In the current codes, 0.35 is the noted U-factor for Climate Zones 6 and 7 in both tables. Connor said his proposal was designed for energy purposes.
“This is one of those opportunities to save some energy here,” he told the committee.
Culp spoke in favor of the proposal on behalf of the AEC.
“This proposal increases the energy efficiency of windows in the North, and they do it in a way that provides flexibility,” he said. However, opposition was present too. Ken Nittler of Enercomp said he wasn’t sure the change to the code would really provide energy savings.
“You have to be careful. There are many cases in many studies that show that a high solar heat gain product may not offset that [the product] has a worse U-factor,” he said. The glass industry wasn’t silent on the topic either.
“On the 0.32 U-factor, you’re going to really limit the number of normal products that people tend to use,” said Stone.The vote was 10-1 against the proposal.
Minimum and Maximum SGHCs Proposed in Climate Zones 5 through 8
Though ultimately the proposal was disapproved by a vote of 11-0, Culp spoke in favor of it.
“The best glass in the South is the worst glass in the North,” said Culp. “[This proposal] prevents the wrong glass from being used in the North.”
However, the majority who came to the podium was opposed, including Craig Drumheller of the NAHB.
“This proposal creates hard limits when they’re not necessary,” he said.
IRC Committee Denies WDMA Code Change Proposal