What Causes Drywall in a Ceiling to Crack?

Drywall Sheet Installation

• A major problem that causes drywall in a ceiling to crack is when an installer uses too few fasteners to hold the sheets of ceiling drywall in place. Not enough fasteners results in cracks on the outside edges of the drywall sheets, as these edges carry all the weight of the sheets while the middle portions of the sheets droop.

Spaces

• Make sure drywall sheets butt up against one another instead of having large spaces between them. If big spaces are present, you have to increase the amount of joint compound you apply to these areas, thus increasing the chance of producing cracks that result from shrinking. Joint compound must be moist to work effectively and keep cracks from forming.

Expansion

• Roof trusses and wall studs typically contract and expand in different weather conditions, so you might spot a crack in the area where a wall comes into contact with a ceiling. For this reason, avoid connecting the drywall sheet in the ceiling area near a wall closer than a foot from the wall’s edge. This allows the drywall sheet to easily expand and contract without causing cracking.

Tape and Temperature

• Keep the tape that covers the joint compound you apply between the ceiling drywall sheets firm against this joint compound. The edges of the drywall sheets crack if the tape is not secure because drywall sheets have a tendency to shift on their own. Do not apply joint compound in cold temperatures or high humidity as the compound takes longer to dry and does not stick to the drywall or tape as well in cold temperatures. Too much humidity keeps the joint compound from thoroughly drying. Maintain the room temperature at a minimum of 50 degrees Fahrenheit before hanging ceiling drywall sheets. Avoid using space heaters to dry the area as these devices produce moisture.