Small cracks can be repaired by applying plaster.
What causes cracks in drywall ceiling.
Occasionally a ceiling joist or a truss becomes damaged or cracked this weakens the framing member and the ceiling will bow or sag in.
Typically plaster ceiling cracks have two causes.
When the ceiling joist or trusses are undersized for the drywall ceiling weight that they re carrying.
These structural members sit on top of the wall plates and are often connected to the plates with nails.
The best way to repair a crack in drywall is to re tape the joint.
This is a sign of structural damage usually related to a weak wall.
If they are bigger and sections of plaster are falling you will probably have to remove the plaster and replace it with a drywall section.
See if the door or window.
House settling and temperature or moisture fluctuations in an attic which result in the expansion or contraction of framing members.
Then sagging may result and the stress from this may create cracks.
One of the most common causes of cracks in drywall ceilings is related to the roof trusses.
This article describes the common causes of all types of cracks that appear in drywall or gypsum board or plasterboard walls ceilings in building interiors.
Cracks in a drywall ceiling are caused by wood movement in the framing due to shrinkage of improperly dried lumber or seasonal changes in temperature and humidity.
Cracks around door frames windows and the ceiling can also indicate your foundation is settling.
Cracks that cause concern are those which run across the length of a ceiling and then continue down a wall along the same line.
If you live in a home with plaster ceilings and you begin to see cracks they may be caused by moisture and or movement.
Drywall cracks in ceilings or walls.
The common approach is to fill the crack with spackling then paint over it but this is at best a temporary fix since the crack will usually come back as the seasons change.
When the wood rafters expand and contract naturally with changing temperature and humidity it pulls the ceiling joists away from the wall plates.
Ceiling cracks in plaster ceilings.
Causes of cracks in walls.
Illustrations show where cracks are most likely to appear explain why and suggest both repair approaches to drywall cracks and how to prevent cracking in plasterboard or gypsum board.
If you find cracks in these areas beery recommends another test.
