Friday, April 13, 2012

Incredible Journey: Charting the Past, Future of the Air Barrier in the Windy City

Air barriers have come a long way baby!

I hope you’ll forgive the dredging up of the old Virginia Slims advertising catchline and the lack of originality. It’s just that the words make such a good fit for a building technology that has seemingly come out of nowhere to assume major significance in the design and construction professions.

Actually, the air-barrier phenomenon charged not from out of nowhere, but from our frozen neighbor to the north, Canada, not too many years ago. We can thank visionaries from the Dominion, as well as the author of a key address at a national air-barrier conference last week in Chicago, for a good portion of this highly valuable import.

The author we refer to (known to some as the “Godfather” of air barriers in the U.S.) is Wagdy Anis, principal at Wiss, Janney, Elstner Associates Inc., longtime with Shepley Bulfinch in Boston, and current chairman of the Building Enclosure Technology and Environmental Council (BETEC).

Anis, addressing the first national ABAA Conference and Trade Show presented by the Air Barrier Association of America, provided a reminder of just how recent the air-barrier “movement” is, and how far it has indeed come.

Wagdy Anis

But Anis—and the ABAA conference program as a whole—emphatically drove home the message that much remains to be done, in terms of building-code development and dissemination, in terms of design and specification comprehension and translation, and in terms of installation-trade proficiency.

Still, the air-barrier saga is quite a story, as Anis related in his address, “The Genesis of Air Barriers in the U.S.” He talked of early trial and error in New England, essentially the birthplace of the air barrier in buildings in the U.S.—like the engineering oversights that led to a billowing—and failed—roof membrane at the Tufts University Tisch Library, where air-pressure forces also made it impossible to keep the front door shut.

On with the evolution

The U.S. had a great deal of catch-up to do in other areas as well; still does, in fact, in terms of building-code requirements and, hopefully, consistency. Massachusetts enacted the first building code incorporating air-barrier requirements in 2001, long after the Canadian Model National Building Code mandated them in 1985 (with maximum air-permeance requirements added in 1995). Several other states have followed suit, but the process remains in an early phase of development.

Air-barrier advocates have encountered tough uphill sledding in the campaign for building-code recognition in the U.S., although increased attention on energy efficiency, reduced greenhouse-gas emissions and other “sustainability” priorities have helped the cause. Air barriers have found a place in the requirements of bedrock code language such as ASHRAE 90.1, the newest International Energy Conservation Code (IECC), and others.

Early lessons learned: Air barriers and building airtightness presented new challenges for engineers. Shown here is Tufts University’s Tisch Library, where an air-barrier system caused a roof membrane to billow and fail and made it difficult to keep the front door closed.

That said, the requirements remain less demanding than building-science and air-barrier advocates would like to see, in some cases. And the serpentine process of translating model national and international model codes into local, regional or state building codes will need to play out.

Nonetheless, the air-barrier army arrayed in Chicago last week was justified in offering a salute to Anis and hailing the emergence of the air-barrier industry in the U.S. And ABAA leaders such as Current President and Chairman Alec Minné, Executive Director Laverne Dalgleish, longtime ABAA President and conference chairman Len Anastasi, the conference co-chair Marcy Tyler (Tremco Inc.), and others had to be awed with the level of attendance and interest at the event, which delivered an impressive lineup of speakers and content in the first crack at the conference.

And talk about a potent batting order: Conference speakers included such industry authorities as Anastasi (of EXO-TEC Companies); Dalgleish; Lance Robson, Building Envelope Technologies Inc.; Terry Brennan, Camroden Associates Inc.; Vince Cammalleri, Simpson Gumpertz & Heger Inc.; Steve Tratt, Canam Building Envelope Specialists Inc.; Andre Desjarlais, Oak Ridge National Laboratory; and other power hitters.

More information on the conference, and other ABAA activities and programs, can be found at the association website, www.airbarrier.org, with conference program details located at ABAA Conference & Trade Show.

We will strive to share more information about the topics addressed at the conference in D+D News, at durabilityanddesign.com, and in our print magazine Durability + Design.

As Wagdy Anis’s telling of the story shows, the air-barrier movement has come a long way since that billowing roof membrane at Tufts University.  And we’re not just blowing smoke.