Why does mould-like growth keep returning in my bathroom?
Recurring growth means moisture remains long enough for regrowth, often from weak exhaust, cold surfaces, leaks, or incomplete drying.
Urgency: moderate
What this means
Address moisture and ventilation before repainting or repeatedly cleaning the surface.
Safe checks
- Run the exhaust during bathing and afterward
- verify airflow at the grille
- dry wet surfaces
- inspect caulk and accessible plumbing.
Stop and get help if
- Seek professional help for extensive or hidden growth, contaminated porous materials, ongoing leaks, or vulnerable occupants.
Which professional to call
Contact the matched licensed or qualified trade if safe checks do not resolve the issue.
Find the relevant tradeSource and method
This answer combines HomeSOS's structured triage with safety boundaries supported by a public source. It does not replace inspection.
Health Canada: Home safety and indoor air guidanceReviewed August 12, 2026