Under NBCC/BCBC, when can you omit the capillary break, and how do you document that performance path?
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If you can show that your setup deals with water well with test results, drawings, and a good explanation then you don’t need the capillary break.
To determine when a capillary break can be omitted under the National Building Code of Canada (NBCC) or British Columbia Building Code (BCBC), we’d typically need to consult specific sections related to building envelope design, moisture management, or seismic design.
You can omit a capillary break only if a tested or code accepted assembly safely handles moisture. Document with detailed drawings, referenced standards/tests, and engineer/architect sign-off.
You can omit a capillary break if sheathing and cladding allow drying, wall is vented, and exposure is low.
Documenting: show wall section drawings, material specs, climate zone, and hygrothermal rationale to justify water management without a gap.
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Under NBCC/BCBC, you can omit a capillary break only in low-exposure zones or via an approved alternative solution. Document with climate data, assembly details, and pro-stamped performance analysis.
Under NBCC/BCBC, you can omit a capillary break only if you prove the assembly meets moisture-control intent without it typically via a performance path like hygrothermal modeling, material testing, and site-specific detailing.
You document it with sealed engineer/architect reports, simulation results (e.g., WUFI), and reference to the applicable code clause in the Alternative Solutions package.
A capillary break can be omitted in certain situations, primarily when it can be demonstrated that its omission will not adversely affect the performance of the building assembly or in the case of specific building types.
Documentation of this performance path involves showing that the chosen alternative meets the intent of the code, which is to protect the building from moisture damage.