Check These Five Things Before Selecting Your Under-Slab Vapor Barrier

Data Sheets Indicate Product Performance. You Need to Know How the Company Behind it Will Perform.


Whether you’re an architect designing a building or a contractor deciphering a specification to bid, you need a certain level of performance out of your product.

The technical data sheet should have all that information, right?

But stellar product performance – and certainly not just numbers and letters on a data sheet – is not the only thing that makes your building material selection a success. Manufacturers should provide more.

When selecting your next below-slab vapor barrier, go beyond the data sheet and evaluate the complete package of your vapor barrier manufacturer. After all, with this selection, you only get one shot at getting this right.

✔ Subject Matter Expertise, Industry Education & A Familiar Face

It’s one thing to simply supply a product – it’s another to enhance the collective technical knowledge of an industry. Industry research, product design, engineering analysis, development of relevant standards, product testing (see QA/QC & Independent Testing below), and extensive, continued training are all things you’d hope a manufacturer in any building materials sector is already doing.

You’d definitely expect the manufacturer to guide you while determining which product or application is right for your project, based on the latest and greatest information. If they know their stuff, the product representative will be in your office (virtually or physically), educating your personnel on the current, unbiased technical information and best practices, and accurately answering your questions.

And wouldn’t it be nice if that representative took that relationship and know-how related to your project into the field? Who else would do a better job educating the construction crew on-site (see Relationships & Site Support below)? Best of all: that site experience closes the loop and comes right back to the design professional’s office!

  • Stego Industries has been a registered AIA CES Provider for over 15 years and a Preferred Education Provider for the ICC since 2014.
  • Stego proudly provides hundreds of AIA-registered Continuing Education Seminars to design professionals every year, in-person or via webinar. Inspectors too! Schedule your next seminar here!
  • Stego’s representatives are trained to exceed the highest quality of educational standards in the AIA's Speaker Agreement and all representatives undergo Continuing Education on all subject matters to ensure accurate information. Our onboarding experience alone is a dedicated process to extensively cover topics from the science of moisture migration, to effective installation, to accurate specification.

✔ QA/QC & Independent Testing – Can a Manufacturer Back Up Their Data?

An in-house testing laboratory allows for… more testing!

With under-slab vapor barrier technologies, you need specialized equipment to run tests like permeance, conditioning, tensile strength and puncture resistance, among a litany of others. By frequently running quality assurance and control tests, a manufacturer can ensure they continually deliver the expected level of performance –that whatever is represented on the data sheet is the same performance as that which is delivered to the job site. Sound reasonable enough? Read on.

It’s also critical (and even often required!) that a third-party laboratory perform (or witness) the testing required by a product’s relevant standard – in the case of under-slab vapor barriers, that’s ASTM E1745 Standard Specification for Plastic Vapor Retarders Used in Contact with Soil or Granular Fill under Concrete Slabs.

Even how a test sample gets sourced – for example, that all samples come from a single product roll – is essential to ensuring that the product tested is (again) representative of what will show up on your next job site. Those test results reported on the data sheet ought to be corroborated by an unbiased party.

There is no governing body policing the vapor barrier industry to determine which manufacturers do indeed complete third-party testing, and which product data sheets are indeed accurate.

Historically, independent testing has indicated some strong discrepancies between what is stated on product data sheets and the performance actually being delivered to the field. Reader be warned: next time that representative is in your office or on your screen, ask how they do their quality assurance and quality control.

✔ The Manufacturer's Track Record & Warranty

Unfortunately, the details of most product failures across categories are never heard because they’re settled out of court, with legally binding non-disclosure agreements, allowing all involved parties to chip in without accepting wrongdoing. Alternatively, failures are often tendered to insurance policies for a quick resolution, despite the subsequent premium hikes which may come from them.

Worse, if blame is assigned and is significant enough to force bankruptcy on the responsible party, sometimes the guilty party might emerge across town under a new name, leaving the rest of the project team holding the bag and asking, “Well, what happened to my warranty?”

Stego-3-Questions-600x300How do you know which products (and manufacturers) aren’t failing? Rely on track record: how long has the company been around? What does the fine print of the warranty include? Can they back it up in the event of a failure?

  • Stego Industries has been in business over 20 years as the first manufacturer to market an ASTM E1745-compliant vapor barrier.
  • Backed by billions square feet of material installed without a single reported product failure, Stego now provides an industry-first Life of the Building™ Warranty on our Stego Wrap films.

✔ Relationships & Site Support Offerings

A good manufacturer should want you to get the product installed correctly, right? They should have both the means to complete an effective installation and the know-how to guide you in getting the job done efficiently, all without driving up the cost of your project!

  • Scenario: you’re installing an(y) under-slab vapor barrier on your project. There’s a particular condition on site that has everyone scratching their heads. It’s questionable whether the substitute barrier you’re considering even has a product to meet the standard installation criteria (have you read ASTM E1643?). Who to call? Ideally, the product representative is sitting in the job site trailer for a pre-construction meeting with all relevant parties before work has even begun!
  • They provide training on governing standards and project-specific conditions and analysis on the cost/benefit of potential solutions.
  • They have solutions! The suite of innovative accessory products gives the installer options to choose from to best suit the needs of their crew and the conditions on-site.
  • They arm your project team with efficient resources: CAD Drawings, BIM content, product samples, and product certifications alongside full submittal documentation.
  • Finally: are they able to review the work performed? The manufacturer should be available to review representative portions of the barrier installation prior to concrete placement to ensure compliance with contract documents, even providing an installation review letter to document the occurrence and certify representative portions of the installation. Stego’s Installation Support Program has fostered relationships with contractors to make Stego Wrap the most selected and installed vapor barrier in the country.

✔ Does the Manufacturer Lead by Example with Green Initiatives?

“Sustainability” can be an ambiguous term, but the industry’s goals for the built environment are clear: designing and constructing more efficient buildings that consume less energy, use fewer natural resources, use renewable resources, are safe for occupants, and produce less pollution (before, during, and after construction).

When it comes to sustainability, the advantages of using a below-slab vapor barrier to improve things like indoor air quality and latent moisture load are already clear, but if not, check out this article about how an under-slab vapor barrier contributed to a net-zero classification.

A manufacturer should understand and support these “green” initiatives. To start, a manufacturer should probably have a data sheet – a LEED data sheet, that is, one that communicates if/how the product fits into the scope of the intent of LEED and its relevant credits. Can they also provide transparency into their products with a Health Product Declaration (HPD)?
There are a lot of sustainable building programs, standards and databases out there – check to see if your vapor barrier manufacturer is participating.

Of course, to go beyond the data sheet, a manufacturer should put these initiatives into practice, not just into their products. Sustainable product solutions are only the first step, and staying abreast of the ever-shifting sustainability movement may only be lip service. Manufacturers should also incorporate sustainability into everything they do.

Fuel efficiency programs, carbon offset purchases, sustainable catering options, and 100 percent solar power at corporate locations are all small examples of how Stego minimizes our Stego Footprint.


When Selecting Your Building Products, Consider the Full Package

Specifying and selecting the right product are both important steps to protect your concrete slab and building envelope. Setting proper expectations and executing a successful installation require additional -- often stricter -- attention.

Check-These-Five-Things-600x330If your attention around under-slab vapor barriers is solely focused on price per square foot, you’re likely to fall victim to the old adage, “You get what you pay for.” If you’re aware enough to evaluate product performance and utility, your analysis may still miss both the potential value that could enhance -- and the costly pitfalls that could plague – your project by not going beyond the data sheet.

We know the responsibilities of project design teams are much, much more than this. You deserve more than a data sheet to be successful.

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Dan Marks

Written by Dan Marks

Dan Marks was the former Technical Director at Stego Industries, LLC.

Stego, Stego-Consideration

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