The 3rd potential cause is ghosting which is not actually mold though it can look very similar.
Ceiling no attic without drywall mold.
How to avoid condensation leaks attic mold insulation mold structural damage to roof framing when roof venting is not possible cathedral roof and knee wall insulation venting air path options in older homes hot roof designs.
The attic floor which is the ceiling of the living space below often already is insulated.
If it is and you plan to provide heating and cooling to the finished attic space you need to remove.
Drywall produces a hollow sound when you bump it and doesn t hold well to water damage or in high traffic rooms.
It s fragile easily damaged and a prime breeding ground for mold and bacteria.
Suggestions for un vented or hard to vent building roof cavities.
Worries about the hot roof un vented cathedral ceiling designs how to.
How to fix ceiling condensation.
It s important to do a thorough inspection of the nearby area to determine if mold is present.
Purchase an inexpensive rh meter and monitor the humidity levels in the room.
Condensation on your ceiling can cause water damage and promote the growth of mold or mildew.
Improper ventilation and insulation of home attic space can produce.