EC26 Sparks Debate; Approved as Modified

The International Code Council's Final Action Hearings experienced a stalled pace earlier this week when it reached EC26 of the International Energy Conservation Code (IECC). The proposal generated an abundance of interest and dragged out discussions for nearly half an hour. Discussions especially slowed amid public comment number four. A back and forth session among attendees included debate over a possible conflict between impact-resistant requirements and energy codes.

As submitted, EC26 would effectively change the glazed fenestration solar heat gain coefficient (SHGC) from 0.37 in climate zones one and two to 0.35, and from 0.40 to 0.35 in zone three. Committee action, which was approved yesterday, however, called for a 0.30 requirement across all zones.

The committee stated previously that it believed a 0.30 maximum SHGC rating for fenestration in these zones was reasonable. It further reported that it believed an ample number of products are available to achieve this value. The committee suggested that its move to go from 0.35 to 0.30 reflected a more aggressive value that would be consistent with the level of stringency that present energy conservation concerns call for.

The committee heard debate previously from industry representatives stating that 0.35 was more reasonable than the suggested 0.30 from a product availability point of view, but it ultimately decided to stick with its 0.30.

Public Comment One: 0.35 is Reasonable

Public comment number one, provided by Julie Ruth of JRuth Code Consulting who also represented the American Architectural Manufacturers' Association (AAMA), requested approval as submitted and stated:

"As originally submitted, EC26 established a maximum SHGC of 0.35 in Climate Zones one, two and three for residential glazed fenestration in the IECC. This would have been a 12.5-percent reduction in the SHGC. This provided for some reduction in solar heat gain, and hence anticipated cooling load, in the building, while still allowing a certain amount of daylighting through the fenestration products."

Comment one suggested that lowering the SHGC from 0.40 to 0.35 in the IECC would be a reasonable compromise that should result in some net energy savings. Others felt 0.35 wasn't in sync with current needs.

"Unfortunately, since the time the [original] proposal was submitted, it has now become obsolete," said Mike Fischer, representing the Window and Door Manufacturers Association (WDMA). Fischer supported a 0.30 requirement, arguing that requirement changes were moving at a slower pace than industry needs. "Guys, this is a moving target. Please support the 0.30 not the 0.35," he further urged.

Zone Differences

Public comment number two expressed concerns over having the same requirements for zones one, two and three. Issued by Ron Nickson of the National Multi Housing Council, comment two suggested adjusting zones one and two to a 0.35 requirement, while setting a 0.40 requirement for zone 3. Nickson cited full building simulations as a tool for determining requirements. Concerns were expressed by some individuals over the data used, but Nickson rebutted by explaining only one source currently was available.

Public comment number four, supplied by Thomas S. Zaremba, representing Pilkington North America, and Tom Mewbourne, representing AGC Flat Glass North America Inc, proposed modification to the committee's action to afford greater flexibility in the design and use of hurricane resistant-glass that complies with section 1609.1.2 of the International Building Code. Opposing arguments zeroed in on possible conflicts between IRC and IECC requirements and further focused on the need for EC26 to focus on energy conservation needs, not public safety. Fischer voiced concerns in this area as well.

"I think you've been sold a bill of goods today that we need impact resistance," Fischer stated. "People will die this year from house fires, because they're using space heaters and can't afford to pay their energy bills ... let's not bring public safety into this."

Proponents of public comment number four cited a conflict between the use of single-pane, impact-resistant products and proposed energy requirements.

"If you're a designer and you're going to design a piece of glass in a hurricane-prone area, number one you're going to try to minimize the amount of glass," argued Zaremba. "Most of the glass involved in breakage in a hurricane is going to be annealed glass ... it breaks into shards and it can kill you. That's the cause for single panes of glass."

Ultimately discussions over EC26 re-centered on energy conservation.

Vicki Lovell, representing 3M and the Association of Industrial Metallizers, Coaters and Laminators (AIMCAL), suggested a 0.35 requirement would be more reasonable in the current times, arguing that product availability would become an issue at 0.30 requirements.

"Energy efficiency doesn't work if we can't deliver the products," Lovell argued. "If you keep it at 0.35 and a builder wants to exceed code, they can ... this is a minimum that everyone can live with."

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