'Four Performance Requirements for a Stronger Air Barrier (Specification)' #FixConstruction

Four Performance Requirements for a Stronger Air Barrier (Specification)

9/10/2018

The air barrier technology used in today’s construction and mandated by the International Energy Conservation Code (IECC) are firmly grounded in science. That database of knowledge continues to grow at an astounding rate. Research efforts by the Air Barrier Association of America (ABAA) will be presented at the ABAA Conference in 2019, and you will be astounded by how much research and testing that ABAA has been conducting to ensure better knowledge for all.

Currently, air barrier systems are being marketed with having passed only the air barrier part of the testing (ASTM E2357 - Standard Test Method for Determining Air Leakage of Air Barrier Assemblies) and pay little to no attention to the other architectural performance attributes, such as crack bridging, water resistance, adhesion to a substrate and fastener sealability, which when successfully passed, results in an ABAA Evaluated Assembly.

So, what I’m asking you to consider is an upgrade of performance requirements for a better and stronger air barrier specification. Here are my suggestions for ensuring the best possible air barrier performance for your project:

Require that the air barrier system be an ABAA Evaluated Assembly.
Require that the applicator be both Manufacturer approved and ABAA Certified. Why? We have many untrained firms jumping into this business; do you really want your project to be the training job for the subcontractor? According to the ABAA website, there are 300 Certified Applicators nationwide.
Research selections for both your Continuous Insulation and Air Barrier choices to confirm that both products are indeed NFPA-285 Compliant. Too often these Sections are written as a stand-alone and they are not. They must match up and perhaps the easiest way to do this is to choose three suppliers that manufacturer both an air barrier and their own insulation.
Wind Resistance Requirements: This would be specific to your geographical region, which is important in many areas, but critical in hurricane or special wind territories. Our industry requires wind performance testing for low slope roofs and for windows, but not air barriers. Air Barrier performance varies by manufacturer. As a Consultant, I am aware of one manufacturer whose air barrier assembly (ASTM E2357), steel studs 16” OC with exterior gypsum sheathing went up to 190 mph wind (ASTM E330), and at that point there was a structural failure, but the air barrier was still intact. If you’re in a hurricane zone, don’t you want this type of performance? My suggestion is that your specifications reflect some type of wind resistance based on an ASTM E2357 (specimen 2) assembly with the ASTM E330 testing protocol.

Performance requirements for a proper air barrier specification are vital. The above are four of my suggestions as how you can elevate and upgrade your specs. Should you have any questions or comments, I appreciate you commenting below. Thank you for reading.

11 Comments

MARTIN HOUSTON

9/11/2018 10:19:58 am

I would agree that there are merits to requirements 3 and 4. But I take strong issue with items 1 and 2. We have constructed some of the most air tight buildings that our testing agencies have seen, and we have done it without ABAA evaluated assemblies and with non ABAA certified installers. To point #1, an assembly is an assembly. The real performance comes from where one connects assemblies, not in the assemblies itself. And whole building air tightness relies largely on the mechanical system approach- which is to say- duct leakage matters! And as to having ABAA certified installers, how about instead creating simple repeatable details that anyone can build- even trades who don't even know what an air barrier is? After all, the roofer, AB installer, MEP trades, concrete subs among others all contribute to air tightness. And none of those, except for the AB installer would be certified by ABAA.

Roy Schauffele

9/11/2018 11:10:58 am

Thank you for reading the article and for your comments.

Martin Houston

10/3/2018 02:24:01 pm

Roy- this post has generated good discussion. Do you mind if I reference this at Construct? I think there are some good points that would be of value to the larger group at Construct. Thanks for prompting a thoughtful discussion!

10/3/2018 02:55:08 pm

Martin, I'm very complimented that you wish to use my work and as fellow CSIer, please feel free to use the article. Deeply appreciate your professionalism

Cherise Lakeside

9/11/2018 11:41:20 am

Hey stranger! Nice to know you read our blogs and THANK YOU for sharing your expertise and knowledge, which I happen to know is considerable. Looking forward to seeing you at CONSTRUCT!

Dave Sommer link

9/12/2018 03:20:31 am

I agree with your comments above. It may be worth noting that the membrane itself when installed as part of an assembly with non-combustible substrate, insulation and cladding materials will not trigger NFPA 285. Example- CMU back-up, mineral wool insulation and brick veneer. Hope to see you all at CONSTRUCT 2018!

Ryan Dalgleish link

9/14/2018 10:58:37 am

Hi Martin, I wanted to respond with a few comments on this. It is nice to see someone that is able to achieve high levels of airtight building and obviously you do good work to accomplish this. The only problem is that nationwide, there continues to be struggles with installation and a lot of education still needed.

From ABAA's standpoint, there are two things I would like to address in regards to assemblies and qualified trades.

For evaluated air barrier assemblies, ABAA currently has the only standard published that provides a baseline for air barrier materials and systems that goes well beyond code requirements. I am reminded of the importance of this when I look at the testing we did on 20 mils of peanut butter and it met the code requirements for air permeance. The issue with materials is not initial performance, but long term durability for the life of the wall assembly (50 - 100 years depending on building). These materials need to be able to withstand building movement, pressures, moisture changes, changes in temperature, long term adhesion and other realities of the life of the building. ABAA's requirements are more than air permeance and take into account key physical properties that materials need to display. What might be good on day 1, may not be good on day 3,000.

In regards to ABAA installer certification, it sure can't hurt a project. Having trades trained and proving their knowledge through certification requirements provides a good start to a good installation. There are thousands of contractors that install air barriers nationwide and the success you have achieved is not as common as one may think. The ABAA QAP is a voluntary program that is only put into place by the architect and/or owner as another level of quality for a project. We have over 10,000 projects that have specified it and over a 1000 architects that have and continue to specify it, so it does seem to have value to the design community. It is one tool that can be used in conjunction with whole building testing, commissioning, site observation and other QA/QC strategies to achieve a high performance building.

Cory Robbins link

9/13/2018 03:41:44 pm

I have to agree with Martin. Suggestions 3 & 4 are fantastic and should be included in every project, but the specifications about the ABAA are not as helpful. My company is an installer of Air and Vapor Barriers, as well as wall-cladding systems overtop of them, and there is truly a gaping loophole when combining these two installers.
In theory, they should work together well, and everyone should coordinate their efforts through combined shop drawings showing every single penetration in the Air Barrier. This unfortunately does NOT happen in simple Pre-Construction meetings. There needs to be more meat to it. Without the TEETH of a workmanship warranty, the problem will continue to arise and nothing will get fixed. Post-Construction lawyers are having a field day at the end of the projects where a leak is found because all installers have the ability to run from the problem.

This leads back to my article for this blog
http://www.letsfixconstruction.com/blog/building-an-enclosure-warranty
where we suggest a different specification be added to Division 7 specifications for the wall-cladding. It is a great SAFETY NET to:
a. Catch these issues before they happen
b. motivate the subcontractors/installers to work together from fear of returning to fix the issue late
c. pushes installers and envelope consultants to WORK TOGETHER to get the wall right
d. forces installers to take responisbilty for their installs
e. forces installers to cross-train and understand other scopes that interact/attach to their part of the SYSTEM.

Sorry, I am blabbing, but this subject is near and dear to my heart. And EDA Contractors Inc. really thinks we have found the key to the puzzle to fixing this issue. Installers will take on the System-Warranty if it is forced upon them by the architects and we need your help to spread this concept and make it the NEW NORM!

9/14/2018 06:48:15 am

Cory, I do agree with you and as an Industry Group ABAA is working on a variety of these and other items. One thing most people don't realize is that the bulk of ABAA membership is contractors, not manufacturers, a very different group.
Please note, that ABAA has a free newsletter for all that you can sign up for at the ABAA website and as importantly, there is a "Contractor Newsletter" available to ABAA Contractor members.

9/14/2018 09:17:31 am

This is good information, and I appreciate that. I am on my way to sign up for that now. I also just checked out your website, and I look forward to speaking to you in person at CONSTRUCT. Or, heck, whenever you have a free minute.
Thank you for the article.

9/14/2018 11:09:31 am

Hi Corey,

As discussed in the past, what you suggest is great and is one additional thing that can be done to provide a level of comfort in the installation. The problem is the number of contractors that install the whole wall system is minimal in the overall context of the industry. I wish we had more contractors that take a systems approach, but you are probably the minority at this time. Some of our members that install EIFS provide 10 or 15 year labor and material warranties as they do everything. For other cladding systems, the large majority of the wall assembly is done by a variety of trades that specialize in their particular scope. Most problems happen at intersections of window/wall connections and today's window installers and are not air barrier or cladding installers.

I think an industry program that provides warranty would have value and it would be nice if the insurance companies would be willing to back the warranty policies and have the financial resources in place to handle claims. There have been issues of warranty programs going bankrupt due to a high amount of claims, so a program would need to have the financial backing and resources.

Warranty provides another level of comfort, but I feel the focus should be on ensuring that the warranty would never have to be used taken the approach of providing assurance vs. insurance.

Four Performance Requirements for a Stronger Air Barrier (Specification)

Leave a Reply.

About

Get blog post notifications here

Archives

Categories