Plumbing vents: frost, snow and roof termination

Diagnose winter sewer odours/gurgling by distinguishing traps, blockage, sizing, frost/snow and roof-penetration details.

VERT / GREEN = documenter/entretenir · JAUNE / YELLOW = mesurer/vérifier · ROUGE / RED = arrêter et faire valider.

Odours/gurgling only in deep cold
Include vent frost/snow in diagnosis without climbing an icy roof. Vent altered/reduced
Verify sizing/modification under local code. Roof penetration leaks
Treat flashing/enclosure and plumbing as one interface. Route/sizes documented
Keep vent photos before wall closure.

What the professional checks

Diagnose DWV system and pressure balance
Verify termination/flashing and local climate/code

Official sources

CNRC — Code national de plomberie 2025 CNRC — Guide Partie 9

Checked: 2026-08-22

Related path

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These links connect this page to the next useful checks and decisions without repeating the full content.

Start from a symptomOrganize plausible causes, observations, urgency and the right professional.Open →Track water useCompare meter readings and flag unusual changes.Open →Review water resilienceConnect flooding, drainage and future events to building adaptations.Open →Score home resiliencePrioritize water, outages, fire, climate, health and records.Open →Plan site, drainage and utilitiesCoordinate access, water, sewer, wells, septic, grading and site constraints.Open →

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