Indoor air
Musty smell on the first floor
A musty smell that lives on the main floor — especially after the house has been closed up — is one of the most common wet-coast complaints. The source is often under your feet, not in the room you smell it in.
Mold and mildew need moisture and organic material. In coastal BC, that moisture frequently arrives from a damp crawl space, an unvented bath fan, a crushed dryer vent, chronic window condensation, or a past leak that never fully dried inside a wall.
Start with the cheap diagnostics
- Smell after rain versus after a dry week. Weather-linked mustiness points outside or under the house.
- Crawl space. If you can access it safely: standing water, hanging wet insulation, bare soil, or a strong odor at the hatch is a primary lead.
- Bathrooms. Run the fan; confirm it exhausts outdoors, not into the attic.
- Dryer. The outdoor cap should open freely; heavy lint on the exterior hood is a red flag.
- Closets on exterior walls. Cold corners collect condensation in winter heating season.
Bleaching a visible spot on a windowsill does nothing if the crawl is feeding humid air through the floor system.
Crawl spaces on the wet coast
Vented crawls that “breathe” coastal air often stay damp for months. Bare soil releases moisture. Wet insulation sags and stays wet. The smell migrates upward even when the living space feels dry.
Encapsulation, a sealed ground cover, and controlled drying are the usual long-term directions — but only after liquid water from grading and plumbing is under control.
When to bring in help
- Smell returns quickly after cleaning
- Anyone in the home has asthma or immune concerns
- You find widespread growth, wet drywall, or contaminated HVAC
- The crawl shows standing water or repeated wetting
A single surface clean is not an assessment of hidden assemblies.