Air & Moisture Leakage System Opportunities

Posted on 7/22/2020 10:24:02 AM By Paul Bertram

Continuing the discussion regarding the ASC Growth Program, “Grow the Vertical” ‘Voice of the customer’ research report.

To date, my previous blogs regarding this report broke out each market segment including of roof, vertical wall exteriors and interiors individually. While this information is relevant to product specific adhesives and sealants, air and moisture leakage system solutions are gaining the attention of producers, building enclosure specialists, specifiers, and owners from a risk management perspective. These systems typically include a variety of specific functional performance adhesives and sealants and are backed by a system limited warranty.

Some adhesive/sealants system warrantees may focus on a specific part of the design such as system air window sealant system that seals out weather that optimize interior comfort and energy cost savings

Several producers offer customized system solutions backed with 10/20-year comprehensive  warrantees.

These system solutions include transitions of roofing to vertical walls, vertical walls (exterior/interior) to below grade transitions that are relative to ASC’s “Grow the Vertical “ ‘Voice of the Customer Research” regarding expanded market potential.

As building regulations change, new solutions and practices are required. The problem of unintentional air leakage from buildings has grown in recognition with the amendments to Part L in the building codes that requires energy reduction targets to be addressed and the incorporation of mandatory air leakage testing.

One producer stated that testing is showing transitions as a major area for discontinuity.  This is why building teams are starting to take a closer look at it. In response, some producers offer comprehensive building envelope warranty – some refer to as “Leak Free” which covers material, labor and overburden. 

Product verses System Warranties:

Product warranties are from the perspective of the producer warranting to the Building Owner. Building sealants and adhesives product warrantees provides a watertight weather seal for the Warranty Duration Period from the Warranty Effective Date. In order to obtain the warranty, the building owner typically is responsible to ensure:

  • The product is applied in strict compliance with manufacturer’s published or electronic recommended application procedures and in accordance with any project specific recommendations from the manufacturer
  • The product is used with compatible materials and substrates (testing/evaluation is required to obtain this warranty if the surface is not recommended in the manufacturer’s Surface Preparation Guide The product is applied within its stated shelf life.
  • Field adhesion tests are made, documented, retained, and submitted to the manufacturer upon written request as outlined in the Field Adhesion Test Procedure in order to confirm adhesion under site conditions.

The Producer usually states that they shall not be liable for and expressly disclaims any liability for any damage to the contents of the structure or for any consequential or incidental damage…

System Warranties, as an example, one producer offers a 10-Year Limited Warranty for Weatherization Products. Specifically, this warranty applies to all building structures that are less than five (5) stories in height in the US and Canada. In the US only, this also applies to “Low-Rise Multi-Family Residential Buildings” which is defined as an entire building structure that meets ALL listed conditions, based on IBC 2012 International Building Code.

Typical sealant and adhesive product manufacturer warranties are Limited Warranties” per product that typically include: General Requirements, Limitations and Remedies. A system warranty would incorporate a number of products to comprise a specific system solution and comprehensive warranty.

If a project is scalable/repeatable or a size that carries a higher risk burden, several manufacturers, ORNL (National Oak Ridge Laboratories, and private material testing laboratories might be a consideration for system validation testing of functional performance based on required industry standards.

The transitions of Roof to wall, vertical wall (interior/exterior) to below grade is complex building science. Code addresses these complexities with referral to a number of codes and best practices.

I was also referred to research that ORNL (Oak Ridge National Laboratories conducted.

Evaluation of Air Barriers for Residential Buildings ORNL/TM-2013/604. In this project the goal was to increase the knowledgebase on air barriers for residential buildings. To this end, nine air barrier assemblies were evaluated following a modified version of the ASTM E2357 Standard Test Method for determining Air Leakage Rate of Air Barrier Assemblies.

Waterproofing magazine in their article on Below Grade Waterproofing 101, suggest that integral to developing a system solution, understanding of the jobsite itself is critical. The article points to geotechnical reports that will assist and help start to define some of the possible conditions that may have to be considered. Soils, possible contaminants, chemicals, etc. could dramatically affect the performance of some types of adhesives, sealants and waterproofing.

An excellent resource is Whole Building Design Guide; Building Envelope Design Guide from the National Institute of Building Sciences Whole Building Design Guide. This guide for the building envelope includes the below grade basement walls, foundation and floor slab (although these are generally considered part of the building's structural system) so that the envelope includes everything that separates the interior of a building from the outdoor environment. 

I also will mention that participation in BETEC (Building Enclosure Technology and Environmental Council) is worthy of team members for the advancement of building enclosure science.

The BECs (Building Enclosure Councils) are localized chapters that encompass building enclosure specialists, architects, specifiers, producers/suppliers, contractors, building owners, and universities (educators)

M. Steven Doggett, PhD, also posts really great research by analyzing complex building enclosure failures and materials particularly those involving air, heat, and moisture transport. 

Last, here are some additional considerations:

In the 2020 McKinsey Study: The next normal in Construction
Nine shifts were identified in this study that predict radical change in the way construction projects are delivered.  Examples included: project sustainability requirements, Covid19 impacts, increasing cost pressures, lack of skilled labor, new materials, industrial approaches, digitalization, and new breeds that looks set to transform the value chain. Additionally, the report mentions productization and specialization, increased value-chain control.

Examples that I see fitting into this blog discussion include:

  • Increasing use of Modular Off-Site Construction – the ICC noticed this trend and is currently developing an Off-Site Modular Construction Building Code.
  • Precast producers and others that are turnkey design/build entities– project design, production of the system, testing, and construction of final design all under one entity.
  • Adhesive and Sealant manufacturers offering weather tight system solutions.
    • Applicable in this discussion for transitions from roof to vertical wall (exterior/interior), vertical wall to below grade.
  • Use of drones for field Quality Assurance/Control to monitor various aspects of construction/installations.
  • Increased Association/ Company training programs in building science and installation.
    • Example:
      ABAA’s launch of the Certified Air Barrier Specialist (CABS) training manual (the CABS certification test is now available
    • IIBEC International Institute of Building Enclosure IIBEC offers a certification program in accordance with ISO 17024 for a Certified Building Enclosure Commissioning Provider (CBECxP®). This accredited certification will is based on the following standards: ASTM E2813, Standard Practice for Building Enclosure Commissioning; ASTM E2947, Standard Guide for Building Enclosure Commissioning


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