Best Friend  
Want to Avoid Air Leakage? Chum Up to  
Air Barrier Suppliers, Consultants and More  
by Ellen Rogers  
says John Runkle,vice president,build-  
While advances in high-performance  
That’s not my job.”  
ing sciences with Intertek Building and glazing provide the building and con-  
That’s a phrase no one wants to Construction in York, Pa. “No trade struction industry with hundreds of  
hear—especially on the jobsite. Build- wants to stand out in a negative way.” energy-efficient material options,what  
ing envelope repair can be a multi-bil- Considerations such as the window- about opaque wall assemblies and their  
lion dollar industry that fixes the many to-wall interface as well as material connection to the windows? Uncon-  
problems related to air and/or moisture compatibility are critical when it comes trolled air infiltration is becoming a sig-  
leakage. And in some cases, it can be to ensuring air-tight performance. The nificant concern when it comes to  
tough to say who’s to blame.  
The windows are part of the air bar- ness between the windows/curtain-  
rier and a failure of the building results walls and the various surrounding construction specialist with Midland,  
goal is to maintain air and water tight- ensuring envelope performance.  
As Stanley Yee, facade design and  
in dissecting which areas are leaking,” constructions.  
Mich.-based Dow Corning, explains,  
USGlass, Metal & Glazing | May 2016  
Keep This  
in Mind  
Failure of air barrier systems and  
their continuity will make buildings:  
Less healthy  
Less durable  
Energy inefficient  
uncontrolled air infiltration can lead  
to the inability to balance the HVAC  
“In winter if you have uncontrolled  
air leakage warm conditioned air is es-  
caping the building and may lead to  
overheating,” he says, explaining un-  
controlled moisture is another poten-  
tial problem.  
There are many types of air barrier products. This example shows a self-  
This happens often at the interface adhering membrane from fluid applied air barrier to the curtainwall framing  
with the opaque wall and the fenestra-  
tion,” he says.  
And that’s the rub for the glass and  
CaJossleofifnGPlasosinint Newark, N.J., saw installing. Today we are seeing that our  
system is not representative of the  
glazing industry. Where does that re- firsthand what can happen when the whole picture as there is an expecta-  
sponsibility fall? glazing system and air barrier do not tion that the entire wall assembly  
According to Yee, a lot of general interface as they should. In a recent meets a certain standard. The instal-  
contractors and architects are in- retrofit project the fenestration por- lation and design of the air barrier  
creasingly consolidating work into a tion was tested and passed, as did the may be outside of our scope, but we  
single exterior cladding package air barrier system. However, when they still have a level of responsibility to  
where the air barrier work (in part or were tested together as an assembly, make sure what we are installing  
in whole) is lumped into the glazing air leakage occurred.  
contractor’s work. Ian Josloff, vice president of busi- systems. This is often not clear from  
So where you used to see some de- ness development, says from this ex- the bid and contract documents, but  
works with the design of these other  
gree of segregation, that separation of perience his company learned how in the field … you’re part of the team  
trade and knowledge is slowly being important it is to address these con- and I think that’s the new challenge,  
eroded in favor of focus on the build- nection issues and concerns as early making sure our system performs as  
ing exterior performance,” Yee says. as possible.  
At some point in time there will be a “It’s a benefit for everyone to have in- rier systems.”  
performance expectation that’s being terface with a consultant during the bid Runkle agrees and adds that for  
provided.” and design process as opposed to post decades the focus was just on water  
This, for example, may come by way award when you’re trying to make it performance.  
of building enclosure commissioning work in the field,”he says.“If the design “On retrofits in particular is where it  
BECx), which more and more build- requirements are understood during becomes apparent there can be air leak-  
required with the associated air bar-  
ing owners and architects are calling the bid phase you are able to price the age challenges—most are window re-  
for. “The glazier will need to under- work appropriately. When you don’t placements.”  
stand how air barriers work and the have this, you can get into a field situ-  
“You can put the highest rated prod-  
performance requirements associated ation where the responsibility for cer- uct in an opening, but if the surround-  
with them and how it interacts with tain aspects of the work is unclear.”  
ing conditions can’t accommodate it,it’s  
their work. So there needs to be a  
He continues, “As a glazier, our at- a moot issue,” says Josloff.  
basic understanding of general per- tention has typically been focused on  
formance requirements.”  
the performance of the systems we’re  
continued on page 48  
May 2016 | USGlass, Metal & Glazing  
Best Friend  
continued from page 47  
What About Unitized?  
Unitized curtainwall systems offer many advantages, such as simpler instal-  
lations. But they can also mean fewer concerns when it comes to air barriers.  
Tracy Robbins with contract glazing firm Walters & Wolf says unitized cur-  
tainwall incorporates a pressure equalized system so the air barrier is within  
the system itself.  
StOanye Ionf fthoermbesetdsteps contract  
glaziers can take is becoming fa-  
miliar with the different types of  
air barrier materials with which  
they will have to interface. These  
can include self-adhered sheet  
materials, fluid-applied mem-  
branes, mechanically fastened  
commercial building wraps and  
This allows you to create a continuous air barrier that goes from the glass  
to the side of the unit,” he says, further explaining that on these systems each  
unit is basically stacked all together so the wall system is pressure equalized  
and within the system.  
“The engineering and design work is within the system,” he says.  
building wraps.  
“Knowledge is power,”saysYee.“A  
contract glazier can better choose ma-  
KnThoewquYeostuiornSotfuhfofw to make the glazing pocket of the curtainwall sys- terials … depending on the air barrier  
tem,” says Ide.“They draw it into Au- material,their sealant of choice may not  
transition from the air barrier to the tocad and make it look perfect, but in adhere or be compatible. If [the two]  
glazing system is common for many reality it doesn’t go together that way,” don’t stick they won’t perform.Continu-  
parties working on the project.  
Every job is different and when  
working with different air barriers often start a conversation that would being required in the specification.”  
there are different ways to make the take them through a real life mockup. Product awareness, Yee continues,  
he says.  
In a case like this, Ide says they’d ing the performance requirements  
ity of the air barrier is critical to achiev-  
transition,” says Anthony Cinnamon, Fortunately, he adds, most architects can also be helpful when it comes to  
associate principal in the Chicago office have gone away from this method “be- ease of installation.  
of architectural consultants Wiss, Jan- cause everyone now seems to be going  
“A lot of solutions may be sequence  
driven,”he says.In other words,is there  
ney, Elstner Associates.  
with spray-applied [products].”  
But the main challenge, Ide says he a certain order in which the installation  
Cinnamon says integration details of  
the window/curtainwall-to-wall inter- sees, is compatibility. It’s important, he needs to occur?  
face are often one of the biggest chal- says,to know that the caulking the con-  
“If it involves a choreographed situa-  
lenges in new construction. For the tract glazier is using, for example, will tion … it’s even more [important] to  
contract glazier, he says the material work well with the air barrier prod- keep the lines of communication open  
being used within that transition space uct/system. To ensure material com- with other trades and the product and  
is important. He suggests contract patibility, Ide says they will submit system manufactures that support  
glaziers try to identify early on what the samples to their sealant manufacturer those trades. The air barrier require-  
architect, façade consultant, etc. wants to conduct a pull test for approval. This ments will need a lot of communication  
to use and make sure it can be identi- typically takes place during the sub- and coordination— more so than we  
fied in the shop drawings.  
“Find out what they want to use and  
mittal process.  
Runkle says another compatibility  
have been accustomed to in the past.”  
“Conduct mock-up testing as early as  
how to marry it to the glazing system,” consideration is keeping in mind the you can, not only from a constructabil-  
he suggests. “You want to have that in increasing number of products avail- ity sake but also performance sake.  
the bid documents or specifications so able on the market. In terms of Mock up a complete wall with the tran-  
you know what to use. With that, you sealant materials, as well as air barri- sition to see how everything goes to-  
can then start to identify what the is- ers, there are more products now than gether, etc. The earlier on you can do  
sues/concerns might be.”  
Speaking of architectural draw-  
ever before.  
“… Air barrier materials tradition- to hold up construction. Freestanding  
the mock-up the better.You don’t want  
ings, Scott Ide, contract sales man- ally are made from material that’s not mock up transition areas are key and  
ager for Brin Contract Glazing in the same as what sealants are made of. that goes back to pre-construction  
Minneapolis, says these can some- Sometimes they stick well and some- stages when you identified what to use,  
times be challenging.  
times they don’t,” he says. “There’ve where, how, etc.,” says Cinnamon.  
As more and more attention is made  
I’ve seen the architects try to take been increased concerns because there  
something like  
membrane and design it into the rier manufacturers.”  
peel-and-stick are [now so many] sealants and air bar- to the issue of air leakage it will be ben-  
eficial for contract glaziers to have dis-  
USGlass, Metal & Glazing | May 2016  
Ensuring compatibility across the transition membrane from, for example, a fluid applied air barrier sealed to curtainwall  
framing, can help maintain an airtight installation.  
cussions concerning compatibility and  
responsibilities during the bid process formance, you cannot look at an iso- products will interface.  
rather than post award, says Josloff. lated system. We all need to pay more Another matter to keep in mind is  
Mock-ups are terrific, but they are attention to how our individual sys- the growing focus on BECx, which will  
“With the new attention to air per- tance of understanding how different  
to validate the design, not develop it. tem integrates with the surrounding require whole building air leakage test-  
When you modify a design because of a conditions and how that impacts the ing as well as periodic air barrier in-  
mock-up that means there was a prob- overall performance of the exterior spections during construction. This  
lem and that’s not the best way to go to wall assembly,” he says.“We tradition- will ultimately lead to increased atten-  
market,” he says.“If design documents ally look at the performance of what tion to air barriers and the window-  
don’t highlight what’s required, that’s we provide. Today, you can no longer wall details. Straying aware and  
when it becomes a real problem be- isolate the glazing system and look at informed of these changes and devel-  
cause who takes ownership? From our performance as a standalone item. It opments will help contract glaziers stay  
perspective, have consultants involved has to be examined as part of the en- ahead of the curve. s  
during the bid not afterwards so they tire envelope.”  
can guide accordingly.”  
Speaking of his company’s own ex- WKheaept’insmNinedx,ta?ir barriers are not  
the importance of a holistic approach, always a part of every project, but  
Josloff says there will need to be a their use is growing.Building codes  
shift to get the trades to look beyond are increasingly requiring them,  
E l l e n R o g e r s is the  
perience, and what it learned about  
editor of USGlass magazine.  
Follow her on Twitter  
@USGlass and like USGlass  
on Facebook to receive  
their immediate focus.  
which is also driving the impor-  
May 2016 | USGlass, Metal & Glazing