If the ceiling had been insulated the vapor barrier would have.
Attic moisture on drywall ceiling.
Finally and most importantly condensation on ductwork can then drip off of your ducts and feed mold growth.
Second when water condenses and drips off of your ductwork it can cause your ceiling to leak which can rot drywall and cause your ceiling to collapse over time not to mention it looks horrible.
Moisture resistant drywall is called greenrock and is specially treated for use in bathrooms and other damp areas.
Improper ventilation and insulation of home attic space can produce high humidity levels and trap.
This is usually because they have not insulated the attic before beginning the drywall finishing.
House settling and temperature or moisture fluctuations in an attic which result in the expansion or contraction of framing members.
Check local codes for specific requirements of your area.
The next approach to reducing attic moisture is by controlling air infiltration.
The standard panel is 4x8 feet although 10 foot and 12 foot panels are available.
Before the introduction of attic insulation attics in cold climates were poorly insulated and plastic ceiling vapor barriers were omitted.
Moisture from the drywall finishing condenses against the cold plastic and dampens the drywall.
All attics vented or unvented should have an air barrier a properly detailed airtight drywall ceiling for example regardless of climate.
The heat being lost from the house below warmed up the attic so that moisture.
If you notice condensation on your windows and walls find peeling wallpaper or bubbled paint or see mold spots around the house your home s humidity is too high.
However all attics vented or unvented and in all climates should have an air barrier such as an airtight drywall ceiling.
Typically plaster ceiling cracks have two causes.
Omitting a ceiling vapor barrier by arguing that you have to let the moisture escape or because the house has to breathe out the top is actually correct in a way.
Depending on how tight a house is constructed and the outside temperature even a relative humidity of 30 percent may be too high.
At higher levels relative humidity condensation can even occur inside of the house on windows cold walls or ceiling surfaces.
Sometimes your daily activities add more humidity to the air than your home can handle leading to a buildup of moisture.
The most commonly used drywall thicknesses are 1 2 inch and 5 8 inches thick.
When they do the drywall finishing the drywall on the ceiling may sag from moisture.