Majvest exceeds Canadian building code requirements

Building in Canada? See how the Majvest stacks up against Canadian building code.

Building in Canada?

Recent testing and evaluations have determined that the SIGA Majvest exceeds Canadian Building Code requirements. As a result, it might be the ideal water-resistive barrier and air barrier for your façade and roof.

Majvest is a highly vapor-permeable, mechanically-attached WRB used to create a durable exterior air barrier wall assembly, in addition to performing as a robust weather resistive barrier.

The Majvest has undergone a thorough testing process to ensure its ability to surpass Canadian Building Codes.

The Majvest’s functional use as an air barrier material and as a water resistive barrier (sheathing, membrane/house wrap) was tested according to the standards set by the following Canadian building codes:

  • 2015 National Building Code of Canada (NBC)
  • 2012 British Columbia Building Code (BCBC)
  • 2014 Vancouver Building By-Law (VBBL)
  • 2017 Ontario building

These Canadian building codes set the minimum requirements for building materials to comply with. As a result, materials like your WRB are tested to demonstrate compliance with building codes and satisfy the local Authority Having Jurisdiction (AHJ).

SIGA Majvest used as a weather barrer in British Columbia

Testing process: Air barrier material and system requirements for Majvest

The Majvest acts as two primary control functions within exterior walls, to serve as your water resistive barrier and as your air barrier. It was tested as an air barrier material and as part of the air barrier assembly and then compared with the requirements of NBC, BCBC, VBBL and the OBC.

CAN/ULC-S741 Standard for Air Barrier Materials

To satisfy the Canadian building codes requirements for air barrier materials, the Majvest underwent CAN/ULC-S741., Air Barrier Materials testing.

The CAN/ULC-S741 was run on Majvest without accessories and details to determine its performance against air leakage in both directions (infiltration and exfiltration). This was done before and after a conditioning and aging period when the Majvest was exposed to UV radiation and then subjected to heat conditioning

What were the results of the tests?

Majvest met the specified performance requirements of the CAN/ULC-S741.

CAN/ULC-S742 Standard for Air Barrier Assemblies

To satisfy Canadian building code requirements, Majvest underwent the testing to complete the ASTM E2357 Standard Test Method for Determining Air Leakage of Air Barrier Assemblies and the CAN/ULC-S742 Standard for Air Barrier Assemblies.

The tests were performed by CLEB, a Canadian third-party certified testing facility.

Mavest tested for control infiltration air permeance
Mavest tested for control infiltration air permeance

How were the Majvest tests done?

Testing is completed by building two mockups representing the air barrier assemblies as constructed in the field and according to the Majvest installation guidelines.

Mockup 1: Built without any penetrations

Mockup 2: Built with the various penetrations typically found in an exterior wall

Each mock-up was prepared per standard procedures and placed in a test chamber. In this chamber, positive and negative pressures were applied across the assemblies in stages as the airtightness of the barrier and system components are evaluated.

SIGA Majvest underwent air leakage tests on penetrated wall assembly

What were the results of the test?

The Majvest air barrier system exceeded the air leakage recommendation of NBC 2010, NBC 2015 and the ABAA requirements.

Furthermore, the Majvest air barrier system installed with high performance tape SIGA Wigluv, did not show any sign of deterioration or failure after being subjected to the strong wind pressure conditioning and structural tests as per CAN/ULC-S742-11, Clauses 6.3.3 & 6.3.4 and ASTM E2357-11, Clauses 9.2 & 9.4 ABAA requirements.

What does this mean?

The Majvest, installed using Wigluv, was able to withstand sustained, cyclical and gust pressure loading to protect your building’s structural integrity and its occupant’s safety.

The evaluation process:


After reviewing all of the third-party material testing reports, RDH has reported that the Majvest satisfies the performance requirements for both roles, provided the terms in the Usage and Limitations are heeded in their product evaluation report that is


The Majvest has a 30-year field-testing record showing superior air and weather barrier performance. The latest round of testing by a Canadian testing lab further proves its ability to achieve your air and weathertightness goals.

Click here to read RDH’s letter reporting the Majvest’s compliance with necessary building code material requirements.

Click here to learn how to install the SIGA Majvest
Avatar for Jessica Kumor

Jessica Kumor

Jessica is SIGA North America's Marketing Director. It's her job to deliver you the latest research and practical tips for building air and weathertight buildings. When she's not interviewing customers and posting about building science you can find her refinishing furniture.

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