White deposits need identification and a moisture assessment. Cleaning the visible mark alone may leave the cause unresolved.
Updated September 10, 2026
Your home in Vancouver.
About 28% of occupied homes in Vancouver heat primarily with utility gas. A chimney in Vancouver may therefore serve an oil, electric, or wood-heated home, so identify the appliance connected to each flue before planning service. About 1.1% of occupied homes in Vancouver use wood as their primary heating fuel. Most fireplaces in Vancouver see occasional use, and even occasional use calls for an inspection before the heating season. The nearest NOAA climate normals station (Portland International Airport, about 3 miles from the Vancouver city center) averages 4,277 heating degree days per year. That is a moderate heating season, but moisture still reaches masonry year-round, so note when water appears and have the source investigated before choosing a surface treatment.
What you can observe safely
- Note whether stains return after rain.
- Photograph the pattern without scraping or applying chemicals.
What to avoid
- Do not climb onto the roof or enter the chimney.
- Do not alter gas components, venting, or safety controls.
- Do not use a test fire to diagnose the problem.
Possible causes to assess
- Moisture movement
- Soluble deposits
- Other surface staining requiring identification
A symptom cannot establish the cause remotely. An assessment of the complete system helps determine the appropriate repair.
Chimney repair in VancouverA few common questions
Can this be diagnosed from a photo?
A photo can document a symptom and help prepare a visit. It cannot confirm concealed conditions or establish that a chimney or fuel-burning appliance is safe.


