What Causes Ghosting?
Ghosting is the slow buildup of air-borne dust, dirt, and soot particles on walls or ceilings. Also known as “ghost stains,” “bridging,” or “thermal tracking,” ghosting creates strange patterns along exterior walls and black spots on ceilings.
Three things generally cause ghosting to form:
-Air passing through the building envelope
-High indoor humidity
Inadequate insulation, gaps in the insulation or exteriors, or the absence of a thermal break allows cold winter air to penetrate inside the wall. Condensation forms, attracting interior air particles to framing and sheetrock fasteners.
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