Roof valley: carry concentrated water without concentrating failures
A valley receives much more water, snow and debris than a typical roof field; repairs must coordinate deck, membrane, flashing, slope and drainage.
Triage only — not a design.
VERT / GREEN · JAUNE / YELLOW · ROUGE / RED
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What the professional checks
The professional checks deck, valley geometry, membrane, flashing, roof-material compatibility, ice/snow, ventilation and drainage.
Official sources
Checked: 2026-08-24
Related path
Continue with the right tools
These links connect this page to the next useful checks and decisions without repeating the full content.
Connect symptoms to the enclosureStart from condensation, staining, odours or movement before choosing a repair.Open →Adapt the enclosure to climateConnect heat, cold, water, wind and wildfire to building priorities.Open →Assess overall resilienceReview water, climate, safety, autonomy and records with a local score.Open →Screen hazardous materialsIdentify situations where work should stop and testing is needed before disturbance.Open →Open climate guidanceReview climate constraints relevant to assemblies and materials.Open →
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